feat(android): QueueScreen rows show artist · album + duration (audit v3 §4.17)

Queue rows only showed title + artist. Now the subtitle reads
"Artist · Album" (collapsing gracefully when either is empty) and a
trailing m:ss duration appears when known — matches Flutter's queue
row density so users can tell tracks apart by album + length.

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

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

@@ -123,9 +123,10 @@ private fun QueueRow(track: TrackRef, isCurrent: Boolean, onClick: () -> Unit) {
                 maxLines = 1,
                 overflow = TextOverflow.Ellipsis,
             )
-            if (track.artistName.isNotEmpty()) {
+            val subtitle = queueSubtitle(track)
+            if (subtitle.isNotEmpty()) {
                 Text(
-                    text = track.artistName,
+                    text = subtitle,
                     style = MaterialTheme.typography.bodySmall,
                     color = MaterialTheme.colorScheme.onSurfaceVariant,
                     maxLines = 1,
@@ -133,7 +134,27 @@ private fun QueueRow(track: TrackRef, isCurrent: Boolean, onClick: () -> Unit) {
                 )
             }
         }
+        if (track.durationSec > 0) {
+            Text(
+                text = formatDuration(track.durationSec),
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
     }
 }
 
+/** "Artist · Album" — collapses gracefully when either is missing. */
+private fun queueSubtitle(track: TrackRef): String = listOf(track.artistName, track.albumTitle)
+    .filter { it.isNotEmpty() }
+    .joinToString(" · ")
+
+private const val SECONDS_PER_MINUTE = 60
+
+private fun formatDuration(seconds: Int): String {
+    val mins = seconds / SECONDS_PER_MINUTE
+    val secs = seconds % SECONDS_PER_MINUTE
+    return "%d:%02d".format(mins, secs)
+}
+
 private const val HIGHLIGHT_ALPHA = 0.12f