fix(android): silent-breakage cluster — search/artist/nowplaying

Three bugs from the v2 parity audit:

* Search: tapping a track result built a single-track queue
  (auto-advance died on track end). Now builds a queue from the full
  visible Loaded tracks list starting at the tapped row, mirroring
  Flutter.
* ArtistDetail: Play button played albums in tracklist order. Flutter
  shuffles. .shuffled() on the fetched list.
* NowPlaying: when the session tore down (queue finished, queue
  cleared from elsewhere) the screen stranded the user on an
  EmptyState with no escape. Replaced with a 500ms-debounced
  popBackStack so the brief null during MediaController IPC bind
  doesn't bounce the user, but a genuine session-end pops them back
  to wherever they came from.

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

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

@@ -73,15 +73,16 @@ class ArtistDetailViewModel @Inject constructor(
     }
 
     /**
-     * Pull every track across the artist's albums and start playing.
-     * Network round-trip per click; fine because the user explicitly
-     * tapped Play and a cache lookup wouldn't be complete anyway
-     * until per-album hydration finishes.
+     * Pull every track across the artist's albums, shuffle, and start
+     * playing. Mirrors Flutter's artist Play button — pressing Play on
+     * an artist is implicitly "shuffle this artist", not "play album by
+     * album in tracklist order". Network round-trip per click; fine
+     * because the user explicitly tapped Play.
      */
     fun playArtist() {
         viewModelScope.launch {
             try {
-                val tracks = repository.fetchArtistTracks(artistId)
+                val tracks = repository.fetchArtistTracks(artistId).shuffled()
                 if (tracks.isNotEmpty()) {
                     player.setQueue(
                         tracks = tracks,

android/app/src/main/java/com/fabledsword/minstrel/player/ui/NowPlayingScreen.kt

@@ -52,7 +52,6 @@ import com.fabledsword.minstrel.player.RepeatMode
 import com.fabledsword.minstrel.nav.AlbumDetail
 import com.fabledsword.minstrel.nav.ArtistDetail
 import com.fabledsword.minstrel.nav.Queue
-import com.fabledsword.minstrel.shared.widgets.EmptyState
 import com.fabledsword.minstrel.shared.widgets.trackactions.TrackActionsButton
 import com.fabledsword.minstrel.shared.widgets.trackactions.TrackActionsViewModel
 import com.fabledsword.minstrel.theme.FabledSwordFlatTokens
@@ -63,6 +62,7 @@ private const val TRANSPORT_ICON_DP = 36
 private const val PLAY_PAUSE_ICON_DP = 56
 private const val MS_PER_SECOND = 1000L
 private const val SECONDS_PER_MINUTE = 60L
+private const val POP_GRACE_MS = 500L
 
 /**
  * Full-screen player. Shows the cover (placeholder until AlbumRef join
@@ -85,10 +85,17 @@ fun NowPlayingScreen(
     }
     val track = state.currentTrack
     if (track == null) {
-        EmptyState(
-            title = "Nothing playing",
-            body = "Pick a track from the library to start.",
-        )
+        // Session torn down (queue finished + auto-stop, or user cleared
+        // the queue from elsewhere). Pop back to whichever shell screen
+        // launched NowPlaying rather than stranding the user on an
+        // EmptyState with no escape. A short delay swallows the
+        // momentary null during MediaController IPC bind on cold-mount.
+        LaunchedEffect(Unit) {
+            kotlinx.coroutines.delay(POP_GRACE_MS)
+            if (viewModel.uiState.value.currentTrack == null) {
+                navController.popBackStack()
+            }
+        }
         return
     }
     Scaffold(

android/app/src/main/java/com/fabledsword/minstrel/search/ui/SearchViewModel.kt

@@ -76,9 +76,22 @@ class SearchViewModel @Inject constructor(
         setQuery("")
     }
 
+    /**
+     * Tapping a search result builds a queue from the full visible
+     * track-results list starting at the tapped entry, matching Flutter.
+     * Falls back to single-track playback when the loaded state isn't
+     * a Success (shouldn't happen in normal flow but keeps the call
+     * safe).
+     */
     fun playTrack(track: TrackRef) {
         if (track.streamUrl.isEmpty()) return
-        player.setQueue(listOf(track), initialIndex = 0, source = "search")
+        val loaded = internal.value.results as? SearchResultsState.Loaded
+        val playable = loaded?.response?.tracks
+            ?.filter { it.streamUrl.isNotEmpty() }
+            ?.takeIf { it.isNotEmpty() }
+            ?: listOf(track)
+        val startIndex = playable.indexOfFirst { it.id == track.id }.coerceAtLeast(0)
+        player.setQueue(playable, initialIndex = startIndex, source = "search")
     }
 
     private suspend fun runSearch(q: String) {