refactor(android): drop bottom nav for AppBar+actions+kebab; shell wrapper (sub-task 2)

Aligns with Flutter — there is no bottom nav, drawer, or rail. Every
in-shell screen carries `MainAppBarActions` in its AppBar:

  [Home] [Library] [Search] [ ⋮ Playlists / Discover / Settings / Admin ]

The icon for the current screen is suppressed so the action set looks
contextual.

  - shared/widgets/MainAppBarActions.kt — NEW. The icon row + kebab.
    Takes navController + currentRouteName (FQN) so each screen tells
    it which icon to hide. Admin kebab entry gated on `isAdmin` for
    later; defaults false.
  - shared/widgets/ShellScaffold.kt — NEW. Wraps any in-shell screen
    with the MiniPlayer pinned at the bottom (auto-hides on no-track,
    matches Flutter `_ShellWithPlayerBar`). Banners slot reserved for
    later (VersionTooOld / UpdateBanner).
  - nav/Routes.kt — added Discover, Playlists, Requests, Admin,
    AdminRequests, AdminQuarantine, AdminUsers, ServerUrl. Grouped
    by shell-vs-full-screen comments.
  - nav/MinstrelNavGraph.kt — every in-shell route wrapped in
    ShellScaffold. NowPlaying becomes a full-screen route with
    slideInVertically/slideOutVertically transitions (mirrors
    Flutter's CustomTransitionPage modal). Queue / ServerUrl / Login
    are also outside the shell.
  - MainActivity.kt — drops Scaffold + NavigationBar + the BottomBarTab
    list. Just hosts the NavHost now. The MiniPlayer moves into
    ShellScaffold per the Flutter pattern.
  - library/ui/LibraryScreen.kt — wraps itself in Scaffold + TopAppBar
    + MainAppBarActions (currentRouteName = Library FQN). Accepts
    navController; album/artist taps navigate via the controller
    instead of via callbacks. Body content still transitional — the
    proper 5-tab restructure lands in sub-task 4.

Routes-without-real-screens (Home, Search, Discover, Playlists,
Settings, Admin, Requests, AdminRequests/Quarantine/Users, Queue,
ServerUrl, Login) all render ComingSoon stubs via EmptyState so the
nav graph is fully reachable end-to-end.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

android/app/src/main/java/com/fabledsword/minstrel/MainActivity.kt

@@ -4,38 +4,13 @@ import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
-import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.padding
-import androidx.compose.material3.Icon
-import androidx.compose.material3.NavigationBar
-import androidx.compose.material3.NavigationBarItem
-import androidx.compose.material3.Scaffold
-import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.graphics.vector.ImageVector
-import androidx.navigation.NavDestination.Companion.hasRoute
-import androidx.navigation.NavHostController
-import androidx.navigation.compose.currentBackStackEntryAsState
 import androidx.navigation.compose.rememberNavController
-import com.composables.icons.lucide.House
-import com.composables.icons.lucide.LibraryBig
-import com.composables.icons.lucide.Lucide
-import com.composables.icons.lucide.Search
-import com.composables.icons.lucide.Settings
-import com.fabledsword.minstrel.nav.Home
-import com.fabledsword.minstrel.nav.Library
 import com.fabledsword.minstrel.nav.MinstrelNavGraph
-import com.fabledsword.minstrel.nav.NowPlaying
-import com.fabledsword.minstrel.nav.Search as SearchRoute
-import com.fabledsword.minstrel.nav.Settings as SettingsRoute
-import com.fabledsword.minstrel.player.ui.MiniPlayer
 import com.fabledsword.minstrel.theme.MinstrelTheme
 import dagger.hilt.android.AndroidEntryPoint
-import kotlin.reflect.KClass
 
 @AndroidEntryPoint
 class MainActivity : ComponentActivity() {
@@ -50,51 +25,11 @@ class MainActivity : ComponentActivity() {
 
 @Composable
 private fun App() {
+    // No bottom nav, no drawer — navigation is per-screen via the
+    // AppBar actions row + kebab (`MainAppBarActions`). The MiniPlayer
+    // is included by each in-shell route's `ShellScaffold` wrap;
+    // full-screen routes (NowPlaying / Queue / unauthenticated) bypass
+    // the shell entirely.
     val navController = rememberNavController()
-    Scaffold(
-        modifier = Modifier.fillMaxSize(),
-        bottomBar = {
-            // MiniPlayer sits above the bottom nav. It hides itself
-            // (Composable returns nothing) when no track is loaded.
-            Column(modifier = Modifier.fillMaxWidth()) {
-                MiniPlayer(onExpandClick = { navController.navigate(NowPlaying) })
-                MinstrelBottomBar(navController)
-            }
-        },
-    ) { inner ->
-        MinstrelNavGraph(
-            navController = navController,
-            modifier = Modifier.padding(inner),
-        )
-    }
-}
-
-private data class BottomBarTab(
-    val label: String,
-    val icon: ImageVector,
-    val routeClass: KClass<*>,
-    val navigate: NavHostController.() -> Unit,
-)
-
-@Composable
-private fun MinstrelBottomBar(navController: NavHostController) {
-    val tabs = listOf(
-        BottomBarTab("Home", Lucide.House, Home::class) { navigate(Home) },
-        BottomBarTab("Library", Lucide.LibraryBig, Library::class) { navigate(Library) },
-        BottomBarTab("Search", Lucide.Search, SearchRoute::class) { navigate(SearchRoute) },
-        BottomBarTab("Settings", Lucide.Settings, SettingsRoute::class) { navigate(SettingsRoute) },
-    )
-    val backStackEntry by navController.currentBackStackEntryAsState()
-    val currentDestination = backStackEntry?.destination
-    NavigationBar {
-        tabs.forEach { tab ->
-            val selected = currentDestination?.hasRoute(tab.routeClass) == true
-            NavigationBarItem(
-                selected = selected,
-                onClick = { tab.navigate(navController) },
-                icon = { Icon(tab.icon, contentDescription = tab.label) },
-                label = { Text(tab.label) },
-            )
-        }
-    }
+    MinstrelNavGraph(navController = navController, modifier = Modifier.fillMaxSize())
 }

android/app/src/main/java/com/fabledsword/minstrel/library/ui/LibraryScreen.kt

@@ -11,8 +11,11 @@ import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.LazyRow
 import androidx.compose.foundation.lazy.items
 import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Alignment
@@ -20,44 +23,71 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.unit.dp
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.navigation.NavHostController
 import com.fabledsword.minstrel.library.widgets.AlbumCard
 import com.fabledsword.minstrel.library.widgets.ArtistCard
 import com.fabledsword.minstrel.models.AlbumRef
 import com.fabledsword.minstrel.models.ArtistRef
+import com.fabledsword.minstrel.nav.AlbumDetail
+import com.fabledsword.minstrel.nav.ArtistDetail
+import com.fabledsword.minstrel.nav.Library
 import com.fabledsword.minstrel.shared.widgets.EmptyState
 import com.fabledsword.minstrel.shared.widgets.ErrorRetry
+import com.fabledsword.minstrel.shared.widgets.MainAppBarActions
 
 /**
- * Top-level Library tab. Renders horizontally-scrolling rows of
- * Artists and Albums driven by `LibraryViewModel`'s UiState.
+ * Library tab. Currently a transitional shape — Artists row + Albums
+ * row — until sub-task 4 of the design-drift correction replaces the
+ * body with the proper 5-tab TabBar (Artists / Albums / History /
+ * Liked / Hidden) matching Flutter.
  *
- * Loading shows a centered spinner; Empty / Error use the shared
- * widgets; Success renders the lists. Detail-screen navigation
- * (`onArtistClick` / `onAlbumClick`) is wired by the caller — Phase 5.5
- * adds the nav graph + routes.
+ * This commit's sub-task wires the AppBar + MainAppBarActions row so
+ * the screen is reachable via the icon row and detail-screen taps
+ * route through the navController.
  */
+@OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun LibraryScreen(
-    onArtistClick: (ArtistRef) -> Unit = {},
-    onAlbumClick: (AlbumRef) -> Unit = {},
+    navController: NavHostController,
     viewModel: LibraryViewModel = hiltViewModel(),
 ) {
-    val state by viewModel.uiState.collectAsStateWithLifecycle()
-    when (val s = state) {
-        LibraryUiState.Loading -> LoadingCentered()
-        LibraryUiState.Empty -> EmptyState(
-            title = "Nothing here yet",
-            body = "Scan a folder in your server settings to populate the library.",
-        )
-        is LibraryUiState.Error -> ErrorRetry(
-            message = s.message,
-            onRetry = { /* Wired in Phase 5.5 — for now, surface only. */ },
-        )
-        is LibraryUiState.Success -> LibrarySuccessContent(
-            state = s,
-            onArtistClick = onArtistClick,
-            onAlbumClick = onAlbumClick,
-        )
+    Scaffold(
+        modifier = Modifier.fillMaxSize(),
+        topBar = {
+            TopAppBar(
+                title = { Text("Library") },
+                actions = {
+                    MainAppBarActions(
+                        navController = navController,
+                        currentRouteName = Library::class.qualifiedName,
+                    )
+                },
+            )
+        },
+    ) { inner ->
+        val state by viewModel.uiState.collectAsStateWithLifecycle()
+        Box(modifier = Modifier.fillMaxSize().padding(inner)) {
+            when (val s = state) {
+                LibraryUiState.Loading -> LoadingCentered()
+                LibraryUiState.Empty -> EmptyState(
+                    title = "Nothing here yet",
+                    body = "Scan a folder in your server settings to populate the library.",
+                )
+                is LibraryUiState.Error -> ErrorRetry(
+                    message = s.message,
+                    onRetry = { /* Wired in Phase 12 sync controller. */ },
+                )
+                is LibraryUiState.Success -> LibrarySuccessContent(
+                    state = s,
+                    onArtistClick = { artist ->
+                        navController.navigate(ArtistDetail(artist.id))
+                    },
+                    onAlbumClick = { album ->
+                        navController.navigate(AlbumDetail(album.id))
+                    },
+                )
+            }
+        }
     }
 }
 

android/app/src/main/java/com/fabledsword/minstrel/nav/MinstrelNavGraph.kt

@@ -1,5 +1,7 @@
 package com.fabledsword.minstrel.nav
 
+import androidx.compose.animation.slideInVertically
+import androidx.compose.animation.slideOutVertically
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
@@ -10,80 +12,142 @@ import androidx.navigation.toRoute
 import com.fabledsword.minstrel.library.ui.LibraryScreen
 import com.fabledsword.minstrel.player.ui.NowPlayingScreen
 import com.fabledsword.minstrel.shared.widgets.EmptyState
+import com.fabledsword.minstrel.shared.widgets.ShellScaffold
 
 /**
- * Single NavHost for the whole app. Top-level tabs (Home / Library /
- * Search / Settings) are direct destinations; detail screens push on
- * top with their argument types passed via the @Serializable route
- * classes' fields.
+ * App NavHost. Mirrors the Flutter split between shell routes (wrapped
+ * by `_ShellWithPlayerBar` → banners + screen + MiniPlayer) and
+ * top-level non-shell routes (NowPlaying / Queue / unauthenticated).
  *
- * Stub composables call EmptyState — the real screens land in their
- * respective feature phases.
+ * Per-route transition: only NowPlaying gets the modal slide-up; the
+ * rest use the default fade.
  */
 @Composable
 fun MinstrelNavGraph(
     navController: NavHostController,
     modifier: Modifier = Modifier,
 ) {
+    val expandPlayer = { navController.navigate(NowPlaying) }
+
     NavHost(
         navController = navController,
         startDestination = Library,
         modifier = modifier.fillMaxSize(),
     ) {
-        // ── Top-level tabs ────────────────────────────────────────────────
+        // ── In-shell top-level destinations ───────────────────────────
 
-        composable<Home> { ComingSoon(title = "Home", body = "Lands in Phase 6.") }
-
-        composable<Library> {
-            LibraryScreen(
-                onArtistClick = { artist -> navController.navigate(ArtistDetail(artist.id)) },
-                onAlbumClick = { album -> navController.navigate(AlbumDetail(album.id)) },
-            )
+        composable<Home> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Home", "Lands in the next design-drift sub-task.")
+            }
         }
 
-        composable<Search> { ComingSoon(title = "Search", body = "Lands in a later phase.") }
+        composable<Library> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                LibraryScreen(navController = navController)
+            }
+        }
 
-        composable<Settings> { ComingSoon(title = "Settings", body = "Lands in Phase 11.") }
+        composable<Search> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Search", "Lands in a later phase.")
+            }
+        }
 
-        // ── Detail / overlay screens ──────────────────────────────────────
+        composable<Discover> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Discover", "Lands in Phase 10 (Lidarr requests).")
+            }
+        }
+
+        composable<Playlists> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Playlists", "Lands in Phase 7.")
+            }
+        }
+
+        composable<Settings> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Settings", "Lands in Phase 11.")
+            }
+        }
+
+        composable<Admin> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Admin", "Admin landing — lands in a later phase.")
+            }
+        }
+
+        composable<Requests> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Requests", "Your Lidarr requests — Phase 10.")
+            }
+        }
+
+        // ── In-shell detail screens (push-on-top) ─────────────────────
 
         composable<AlbumDetail> { backStackEntry ->
             val route: AlbumDetail = backStackEntry.toRoute()
-            ComingSoon(
-                title = "Album",
-                body = "Album detail for ${route.id} — lands in a later 5.x slice.",
-            )
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Album", "Album detail for ${route.id} — later 5.x slice.")
+            }
         }
 
         composable<ArtistDetail> { backStackEntry ->
             val route: ArtistDetail = backStackEntry.toRoute()
-            ComingSoon(
-                title = "Artist",
-                body = "Artist detail for ${route.id} — lands in a later 5.x slice.",
-            )
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Artist", "Artist detail for ${route.id} — later 5.x slice.")
+            }
         }
 
         composable<PlaylistDetail> { backStackEntry ->
             val route: PlaylistDetail = backStackEntry.toRoute()
-            ComingSoon(
-                title = "Playlist",
-                body = "Playlist detail for ${route.id} — lands in Phase 7.",
-            )
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Playlist", "Playlist detail for ${route.id} — Phase 7.")
+            }
         }
 
-        composable<NowPlaying> { NowPlayingScreen() }
-        composable<Queue> { ComingSoon(title = "Queue", body = "Lands in Phase 6.") }
-        composable<Login> { ComingSoon(title = "Sign in", body = "Lands in a later phase.") }
+        composable<AdminRequests> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Admin · Requests", "Lands with admin slice.")
+            }
+        }
+        composable<AdminQuarantine> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Admin · Quarantine", "Lands with admin slice.")
+            }
+        }
+        composable<AdminUsers> {
+            ShellScaffold(onExpandPlayer = expandPlayer) {
+                ComingSoon("Admin · Users", "Lands with admin slice.")
+            }
+        }
+
+        // ── Outside-shell full-screen routes ──────────────────────────
+
+        composable<NowPlaying>(
+            // Slide up from the bottom on enter; back down on dismiss.
+            // Mirrors the Flutter CustomTransitionPage (280ms easeOutCubic).
+            enterTransition = { slideInVertically(initialOffsetY = { it }) },
+            exitTransition = { slideOutVertically(targetOffsetY = { it }) },
+            popEnterTransition = { slideInVertically(initialOffsetY = { it }) },
+            popExitTransition = { slideOutVertically(targetOffsetY = { it }) },
+        ) {
+            NowPlayingScreen()
+        }
+
+        composable<Queue> { ComingSoon("Queue", "Lands in a later 6.x slice.") }
+
+        composable<ServerUrl> {
+            ComingSoon("Connect to your Minstrel", "Server-URL entry — Phase 11.")
+        }
+        composable<Login> {
+            ComingSoon("Sign in", "Login flow — Phase 11.")
+        }
     }
 }
 
 @Composable
 private fun ComingSoon(title: String, body: String) {
-    // Reuse EmptyState as a generic placeholder for unbuilt screens —
-    // keeps the design system intact rather than ad-hoc Text.
-    EmptyState(
-        title = title,
-        body = body,
-        modifier = Modifier.fillMaxSize(),
-    )
+    EmptyState(title = title, body = body, modifier = Modifier.fillMaxSize())
 }

android/app/src/main/java/com/fabledsword/minstrel/nav/Routes.kt

@@ -2,19 +2,30 @@ package com.fabledsword.minstrel.nav
 
 import kotlinx.serialization.Serializable
 
-// Top-level destinations (bottom-bar tabs).
+// ── In-shell top-level destinations (reachable from MainAppBarActions
+// icons + kebab) ──────────────────────────────────────────────────────
 
 @Serializable data object Home
 @Serializable data object Library
 @Serializable data object Search
+@Serializable data object Discover
+@Serializable data object Playlists
 @Serializable data object Settings
+@Serializable data object Admin
+@Serializable data object Requests
 
-// Push-on-top destinations (no bottom-bar entry).
+// ── In-shell detail / push-on-top destinations ────────────────────────
 
 @Serializable data class AlbumDetail(val id: String)
 @Serializable data class ArtistDetail(val id: String)
 @Serializable data class PlaylistDetail(val id: String)
+@Serializable data object AdminRequests
+@Serializable data object AdminQuarantine
+@Serializable data object AdminUsers
 
-@Serializable data object NowPlaying
-@Serializable data object Queue
-@Serializable data object Login
+// ── Outside-shell full-screen routes ──────────────────────────────────
+
+@Serializable data object NowPlaying      // slide-up modal transition
+@Serializable data object Queue           // standard push
+@Serializable data object ServerUrl       // unauthenticated layer
+@Serializable data object Login           // unauthenticated layer

android/app/src/main/java/com/fabledsword/minstrel/shared/widgets/MainAppBarActions.kt

@@ -0,0 +1,94 @@
+package com.fabledsword.minstrel.shared.widgets
+
+import androidx.compose.foundation.layout.Row
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.navigation.NavHostController
+import com.composables.icons.lucide.House
+import com.composables.icons.lucide.LibraryBig
+import com.composables.icons.lucide.Lucide
+import com.composables.icons.lucide.MoreVertical
+import com.composables.icons.lucide.Search as SearchIcon
+import com.fabledsword.minstrel.nav.Admin
+import com.fabledsword.minstrel.nav.Discover
+import com.fabledsword.minstrel.nav.Home
+import com.fabledsword.minstrel.nav.Library
+import com.fabledsword.minstrel.nav.Playlists
+import com.fabledsword.minstrel.nav.Search as SearchRoute
+import com.fabledsword.minstrel.nav.Settings as SettingsRoute
+
+/**
+ * The universal navigation surface for every shell screen — Flutter's
+ * `MainAppBarActions`. There is no bottom nav, drawer, or rail; every
+ * top-level AppBar carries this row, and the kebab covers the rest.
+ *
+ *   [Home] [Library] [Search] [ ⋮ Playlists / Discover / Settings / Admin ]
+ *
+ * The icon for the screen the user is currently on is suppressed so
+ * the action set looks contextual.
+ *
+ * `currentRouteName` is a soft string match against the destination
+ * route name (route classes serialize to their FQN by default in
+ * nav-compose); pass `Home::class.qualifiedName` etc. from the screen.
+ */
+@Composable
+fun MainAppBarActions(
+    navController: NavHostController,
+    currentRouteName: String?,
+    isAdmin: Boolean = false,
+) {
+    Row {
+        if (currentRouteName != Home::class.qualifiedName) {
+            IconButton(onClick = { navController.navigate(Home) }) {
+                Icon(Lucide.House, contentDescription = "Home")
+            }
+        }
+        if (currentRouteName != Library::class.qualifiedName) {
+            IconButton(onClick = { navController.navigate(Library) }) {
+                Icon(Lucide.LibraryBig, contentDescription = "Library")
+            }
+        }
+        if (currentRouteName != SearchRoute::class.qualifiedName) {
+            IconButton(onClick = { navController.navigate(SearchRoute) }) {
+                Icon(Lucide.SearchIcon, contentDescription = "Search")
+            }
+        }
+        OverflowMenu(navController = navController, isAdmin = isAdmin)
+    }
+}
+
+@Composable
+private fun OverflowMenu(navController: NavHostController, isAdmin: Boolean) {
+    var expanded by remember { mutableStateOf(false) }
+    IconButton(onClick = { expanded = true }) {
+        Icon(Lucide.MoreVertical, contentDescription = "More")
+    }
+    DropdownMenu(expanded = expanded, onDismissRequest = { expanded = false }) {
+        DropdownMenuItem(
+            text = { Text("Playlists") },
+            onClick = { expanded = false; navController.navigate(Playlists) },
+        )
+        DropdownMenuItem(
+            text = { Text("Discover") },
+            onClick = { expanded = false; navController.navigate(Discover) },
+        )
+        DropdownMenuItem(
+            text = { Text("Settings") },
+            onClick = { expanded = false; navController.navigate(SettingsRoute) },
+        )
+        if (isAdmin) {
+            DropdownMenuItem(
+                text = { Text("Admin") },
+                onClick = { expanded = false; navController.navigate(Admin) },
+            )
+        }
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/shared/widgets/ShellScaffold.kt

@@ -0,0 +1,42 @@
+package com.fabledsword.minstrel.shared.widgets
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import com.fabledsword.minstrel.player.ui.MiniPlayer
+
+/**
+ * Outer shell wrapper for "in-app" routes — banners on top
+ * (conditional, none implemented yet), routed screen filling the
+ * middle, MiniPlayer pinned at the bottom (auto-hides when no track).
+ *
+ * Mirrors the Flutter `_ShellWithPlayerBar` (lib/shared/routing.dart).
+ *
+ * Top-level routes (Home / Library / Search / Discover / Playlists /
+ * Settings / Admin / detail screens) wrap themselves with this.
+ * Full-screen routes (NowPlaying / Queue / ServerUrl / Login)
+ * intentionally do NOT — they fill the entire screen, often with a
+ * back-only AppBar.
+ *
+ * `onExpandPlayer` is the navigate-to-NowPlaying callback; passed
+ * through to MiniPlayer so it doesn't have to know the nav graph.
+ */
+@Composable
+fun ShellScaffold(
+    onExpandPlayer: () -> Unit,
+    modifier: Modifier = Modifier,
+    content: @Composable () -> Unit,
+) {
+    Column(modifier = modifier.fillMaxSize()) {
+        // Banners (VersionTooOld, UpdateBanner) live here once those
+        // mechanisms exist; for now the slot is empty so the layout
+        // matches the Flutter structure 1:1.
+        Box(modifier = Modifier.fillMaxWidth().weight(1f)) {
+            content()
+        }
+        MiniPlayer(onExpandClick = onExpandPlayer)
+    }
+}