feat(android): port cached_resume_state + fix CacheSource enum (M8 4.2 slice 8)

Two related fixes from re-reading the Drift source for slice 8:

  1. The plan called this slice "last_played" but the Drift table is
     `cached_resume_state` — kept Drift's name for cross-reference
     during the port. Single-row JSON-blob pattern (queue, currentIndex,
     positionMs, source) — ResumeController (Phase 6.5) handles the
     Kotlin-side encode/decode so the schema stays stable across
     resume-shape evolution.

  2. CacheSource enum was incomplete: Task 4.1 ported only 3 of the 5
     Drift variants. Added AUTO_LIKED + AUTO_PLAYLIST (used by the
     auto-cache prefetcher to tag cached files by reason — drives the
     bucket eviction priority order INCIDENTAL > AUTO_PREFETCH >
     AUTO_PLAYLIST > AUTO_LIKED > MANUAL).

No data migration needed — schema version is still 1 and we have no
real users yet.

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

android/app/src/main/java/com/fabledsword/minstrel/cache/db/AppDatabase.kt

@@ -9,6 +9,7 @@ import com.fabledsword.minstrel.cache.db.dao.CachedArtistDao
 import com.fabledsword.minstrel.cache.db.dao.CachedLikeDao
 import com.fabledsword.minstrel.cache.db.dao.CachedMutationDao
 import com.fabledsword.minstrel.cache.db.dao.CachedPlaylistDao
+import com.fabledsword.minstrel.cache.db.dao.CachedResumeStateDao
 import com.fabledsword.minstrel.cache.db.dao.CachedPlaylistTrackDao
 import com.fabledsword.minstrel.cache.db.dao.CachedQuarantineDao
 import com.fabledsword.minstrel.cache.db.dao.CachedTrackDao
@@ -19,6 +20,7 @@ import com.fabledsword.minstrel.cache.db.entities.CachedArtistEntity
 import com.fabledsword.minstrel.cache.db.entities.CachedLikeEntity
 import com.fabledsword.minstrel.cache.db.entities.CachedMutationEntity
 import com.fabledsword.minstrel.cache.db.entities.CachedPlaylistEntity
+import com.fabledsword.minstrel.cache.db.entities.CachedResumeStateEntity
 import com.fabledsword.minstrel.cache.db.entities.CachedPlaylistTrackEntity
 import com.fabledsword.minstrel.cache.db.entities.CachedQuarantineEntity
 import com.fabledsword.minstrel.cache.db.entities.CachedTrackEntity
@@ -49,6 +51,7 @@ import com.fabledsword.minstrel.cache.db.entities.SyncMetadataEntity
         CachedQuarantineEntity::class,
         AudioCacheIndexEntity::class,
         CachedMutationEntity::class,
+        CachedResumeStateEntity::class,
     ],
     version = 1,
     exportSchema = true,
@@ -65,4 +68,5 @@ abstract class AppDatabase : RoomDatabase() {
     abstract fun cachedQuarantineDao(): CachedQuarantineDao
     abstract fun audioCacheIndexDao(): AudioCacheIndexDao
     abstract fun cachedMutationDao(): CachedMutationDao
+    abstract fun cachedResumeStateDao(): CachedResumeStateDao
 }

android/app/src/main/java/com/fabledsword/minstrel/cache/db/TypeConverters.kt

@@ -5,13 +5,18 @@ import kotlinx.datetime.Instant
 
 /**
  * Source category for a cached audio file. Mirrors the Drift `CacheSource`
- * enum used by the Flutter client's `audio_cache_index` table.
+ * enum used by the Flutter client's `audio_cache_index` table 1:1.
  *
  * - `MANUAL`: user explicitly pinned (e.g. "save for offline")
- * - `INCIDENTAL`: cached as a side effect of playback streaming
+ * - `AUTO_LIKED`: auto-cached because the track is liked
+ * - `AUTO_PLAYLIST`: auto-cached because it's in a pinned playlist
  * - `AUTO_PREFETCH`: pre-warmed by background prefetch heuristics
+ * - `INCIDENTAL`: cached as a side effect of playback streaming
+ *
+ * Eviction priority order (first to evict): INCIDENTAL → AUTO_PREFETCH
+ * → AUTO_PLAYLIST → AUTO_LIKED → MANUAL.
  */
-enum class CacheSource { MANUAL, INCIDENTAL, AUTO_PREFETCH }
+enum class CacheSource { MANUAL, AUTO_LIKED, AUTO_PLAYLIST, AUTO_PREFETCH, INCIDENTAL }
 
 /**
  * Cross-cutting Room type converters. Registered on `@Database` via

android/app/src/main/java/com/fabledsword/minstrel/cache/db/dao/CachedResumeStateDao.kt

@@ -0,0 +1,23 @@
+package com.fabledsword.minstrel.cache.db.dao
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+import com.fabledsword.minstrel.cache.db.entities.CachedResumeStateEntity
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface CachedResumeStateDao {
+    @Query("SELECT * FROM cached_resume_state WHERE id = 1")
+    suspend fun get(): CachedResumeStateEntity?
+
+    @Query("SELECT * FROM cached_resume_state WHERE id = 1")
+    fun observe(): Flow<CachedResumeStateEntity?>
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun upsert(row: CachedResumeStateEntity)
+
+    @Query("DELETE FROM cached_resume_state")
+    suspend fun clear()
+}

android/app/src/main/java/com/fabledsword/minstrel/cache/db/entities/CachedResumeStateEntity.kt

@@ -0,0 +1,28 @@
+package com.fabledsword.minstrel.cache.db.entities
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+import kotlinx.datetime.Clock
+import kotlinx.datetime.Instant
+
+/**
+ * Single-row snapshot of the last playback session — queue (as JSON),
+ * current index, position, and source tag. Mirrors
+ * `flutter_client/lib/cache/db.dart`'s `CachedResumeState` Drift table.
+ *
+ * Lets a torn-down session (the player's idle/dismissed teardown)
+ * resume on next launch; without it the headset / lock-screen play
+ * button has nothing to act on. The Flutter codebase persists this on
+ * every queue change and reads on cold start.
+ *
+ * The `json` field carries the entire ResumeState shape (queue trackrefs,
+ * currentIndex, positionMs, sourceTag). Kotlin-side deserialization
+ * happens in the ResumeController (Phase 6.5) so the schema stays
+ * stable across resume-shape changes.
+ */
+@Entity(tableName = "cached_resume_state")
+data class CachedResumeStateEntity(
+    @PrimaryKey val id: Int = 1,
+    val json: String,
+    val updatedAt: Instant = Clock.System.now(),
+)