music: use indices in playlist db

Use indices in the playlist database, which should improve perofrmance
a little.

app/src/main/java/org/oxycblt/auxio/music/user/RawPlaylist.kt

@@ -57,6 +57,6 @@ data class RawPlaylist(
 @Entity
 data class PlaylistSongCrossRef(
     @PrimaryKey(autoGenerate = true) val id: Long = 0,
-    val playlistUid: Music.UID,
-    val songUid: Music.UID
+    @ColumnInfo(index = true) val playlistUid: Music.UID,
+    @ColumnInfo(index = true) val songUid: Music.UID
 )

app/src/main/java/org/oxycblt/auxio/playback/persist/PersistenceDatabase.kt

@@ -126,6 +126,7 @@ interface QueueDao {
     suspend fun insertMapping(mapping: List<QueueMappingItem>)
 }
 
+// TODO: Figure out how to get RepeatMode to map to an int instead of a string
 @Entity(tableName = PlaybackState.TABLE_NAME)
 data class PlaybackState(
     @PrimaryKey val id: Int,

app/src/main/res/drawable/ic_playing_indicator_24.xml

@@ -3,9 +3,9 @@
     xmlns:aapt="http://schemas.android.com/aapt">
 
     <!--
-    Yes, this whole file is all 30 frames of Spotify's equalizer animation
-    merged with the material equalizer icon, with each vector inlined using
-    aapt:attr so that it does not clutter the drawable folder.
+    Yes, this whole file is the material equalizer icon influenced by Spotify's
+    equalizer animation with each vector inlined using aapt:attr so that it does
+    not clutter the drawable folder.
     -->
 
     <!-- Frame 1 -->