feat(android): Phase 11 Commit C — Settings screen + sign-out

Closes the auth loop. Settings shows the signed-in username and
server URL, and the sign-out button drops the cookie + clears
currentUser + best-effort POSTs /api/auth/logout.

New:
  - settings/ui/SettingsViewModel.kt — VM + SettingsState (server URL,
    username, signing-out spinner, signed-out latch).
  - settings/ui/SettingsScreen.kt — three cards: Account (signed-in
    username + server URL), About (Minstrel + version from
    BuildConfig.VERSION_NAME + VERSION_CODE), Sign out (error-tinted
    button that spins while in-flight). On signed-out, navigates to
    ServerUrl with `popUpTo(0) { inclusive = true }` so the back
    stack is empty.

Modified:
  - nav/MinstrelNavGraph.kt — Settings route renders the real screen.

Closes Phase 11 modulo cross-restart user-identity persistence —
the cookie survives but `currentUser` is in-memory only, so a fresh
launch with an existing cookie leaves the username blank until the
next sign-in. That's the only known gap; queued as a small
AuthSessionEntity schema add when it surfaces.

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

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

@@ -23,6 +23,7 @@ import com.fabledsword.minstrel.player.ui.NowPlayingScreen
 import com.fabledsword.minstrel.playlists.ui.PlaylistDetailScreen
 import com.fabledsword.minstrel.playlists.ui.PlaylistsListScreen
 import com.fabledsword.minstrel.requests.ui.RequestsScreen
+import com.fabledsword.minstrel.settings.ui.SettingsScreen
 import com.fabledsword.minstrel.shared.widgets.EmptyState
 import com.fabledsword.minstrel.shared.widgets.ShellScaffold
 
@@ -83,7 +84,7 @@ private fun NavGraphBuilder.inShellTopLevel(
     }
     composable<Settings> {
         ShellScaffold(onExpandPlayer = expandPlayer) {
-            ComingSoon("Settings", "Lands in Phase 11.")
+            SettingsScreen(navController = navController)
         }
     }
     composable<Admin> {

android/app/src/main/java/com/fabledsword/minstrel/settings/ui/SettingsScreen.kt

@@ -0,0 +1,163 @@
+package com.fabledsword.minstrel.settings.ui
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.ElevatedCard
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+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.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import androidx.hilt.navigation.compose.hiltViewModel
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.navigation.NavHostController
+import com.composables.icons.lucide.LogOut
+import com.composables.icons.lucide.Lucide
+import com.fabledsword.minstrel.BuildConfig
+import com.fabledsword.minstrel.nav.Settings as SettingsRoute
+import com.fabledsword.minstrel.nav.ServerUrl
+import com.fabledsword.minstrel.shared.widgets.MainAppBarActions
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun SettingsScreen(
+    navController: NavHostController,
+    viewModel: SettingsViewModel = hiltViewModel(),
+) {
+    val state by viewModel.state.collectAsStateWithLifecycle()
+
+    LaunchedEffect(state.signedOut) {
+        if (state.signedOut) {
+            navController.navigate(ServerUrl) {
+                popUpTo(0) { inclusive = true }
+            }
+            viewModel.consumeSignedOut()
+        }
+    }
+
+    Scaffold(
+        modifier = Modifier.fillMaxSize(),
+        topBar = {
+            TopAppBar(
+                title = { Text("Settings") },
+                actions = {
+                    MainAppBarActions(
+                        navController = navController,
+                        currentRouteName = SettingsRoute::class.qualifiedName,
+                    )
+                },
+            )
+        },
+    ) { inner ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(inner)
+                .padding(16.dp),
+            verticalArrangement = Arrangement.spacedBy(16.dp),
+        ) {
+            AccountCard(username = state.username, serverUrl = state.serverUrl)
+            AboutCard()
+            SignOutButton(isSigningOut = state.isSigningOut, onSignOut = viewModel::signOut)
+        }
+    }
+}
+
+@Composable
+private fun AccountCard(username: String, serverUrl: String) {
+    ElevatedCard(modifier = Modifier.fillMaxWidth()) {
+        Column(
+            modifier = Modifier.padding(16.dp),
+            verticalArrangement = Arrangement.spacedBy(4.dp),
+        ) {
+            Text(
+                text = "Account",
+                style = MaterialTheme.typography.titleMedium,
+                color = MaterialTheme.colorScheme.onSurface,
+            )
+            Text(
+                text = if (username.isEmpty()) "Signed in" else "Signed in as $username",
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+            Spacer(Modifier.height(8.dp))
+            Text(
+                text = "Server",
+                style = MaterialTheme.typography.titleSmall,
+                color = MaterialTheme.colorScheme.onSurface,
+            )
+            Text(
+                text = serverUrl,
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis,
+            )
+        }
+    }
+}
+
+@Composable
+private fun AboutCard() {
+    ElevatedCard(modifier = Modifier.fillMaxWidth()) {
+        Column(
+            modifier = Modifier.padding(16.dp),
+            verticalArrangement = Arrangement.spacedBy(4.dp),
+        ) {
+            Text(
+                text = "About",
+                style = MaterialTheme.typography.titleMedium,
+                color = MaterialTheme.colorScheme.onSurface,
+            )
+            Text(
+                text = "Minstrel ${BuildConfig.VERSION_NAME} (${BuildConfig.VERSION_CODE})",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}
+
+@Composable
+private fun SignOutButton(isSigningOut: Boolean, onSignOut: () -> Unit) {
+    Button(
+        onClick = onSignOut,
+        enabled = !isSigningOut,
+        modifier = Modifier.fillMaxWidth(),
+        colors = ButtonDefaults.buttonColors(
+            containerColor = MaterialTheme.colorScheme.errorContainer,
+            contentColor = MaterialTheme.colorScheme.onErrorContainer,
+        ),
+    ) {
+        if (isSigningOut) {
+            CircularProgressIndicator(
+                modifier = Modifier.size(20.dp),
+                color = MaterialTheme.colorScheme.onErrorContainer,
+                strokeWidth = 2.dp,
+            )
+        } else {
+            Box(modifier = Modifier.padding(end = 4.dp)) {
+                Icon(Lucide.LogOut, contentDescription = null)
+            }
+            Text("Sign out")
+        }
+    }
+}

android/app/src/main/java/com/fabledsword/minstrel/settings/ui/SettingsViewModel.kt

@@ -0,0 +1,48 @@
+package com.fabledsword.minstrel.settings.ui
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.fabledsword.minstrel.auth.AuthController
+import com.fabledsword.minstrel.auth.AuthStore
+import dagger.hilt.android.lifecycle.HiltViewModel
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+import javax.inject.Inject
+
+data class SettingsState(
+    val serverUrl: String = "",
+    val username: String = "",
+    val isSigningOut: Boolean = false,
+    val signedOut: Boolean = false,
+)
+
+@HiltViewModel
+class SettingsViewModel @Inject constructor(
+    private val authController: AuthController,
+    authStore: AuthStore,
+) : ViewModel() {
+
+    private val internal = MutableStateFlow(
+        SettingsState(
+            serverUrl = authStore.baseUrl.value,
+            username = authController.currentUser.value?.username.orEmpty(),
+        ),
+    )
+    val state: StateFlow<SettingsState> = internal.asStateFlow()
+
+    fun signOut() {
+        if (internal.value.isSigningOut) return
+        viewModelScope.launch {
+            internal.update { it.copy(isSigningOut = true) }
+            authController.signOut()
+            internal.update { it.copy(isSigningOut = false, signedOut = true) }
+        }
+    }
+
+    fun consumeSignedOut() {
+        internal.update { it.copy(signedOut = false) }
+    }
+}