count a play locally when it is scrobbled

A submitted scrobble now bumps the song's playCount/played and its album
and artist ranks, so the play sorts move without waiting for a sync. The
sync then overwrites them with the server's own numbers, so the
increment cannot double-count.

app/src/test/kotlin/com/subtracks/data/db/LibraryDaoTest.kt

@@ -213,6 +213,25 @@ class LibraryDaoTest {
             )
         }
 
+    @Test
+    fun aRecordedPlayBumpsTheSongAlbumAndArtist() =
+        runTest {
+            val sourceId = source()
+            val dao = db.libraryDao()
+            dao.upsertArtists(listOf(artist(sourceId, "ar-1", "Artist", albumCount = 1)))
+            dao.upsertAlbums(listOf(album(sourceId, "al-1", "Album", year = null, starred = null)))
+            dao.upsertSongs(listOf(song(sourceId, "s1", "One", starred = null)))
+
+            dao.recordPlay(sourceId, "s1", 500)
+
+            assertEquals(1L, dao.songOnce(sourceId, "s1")!!.playCount)
+            assertEquals(500L, dao.songOnce(sourceId, "s1")!!.played)
+            assertEquals(1L, dao.albumOnce(sourceId, "al-1")!!.playCount)
+            assertEquals(500L, dao.albumOnce(sourceId, "al-1")!!.played)
+            assertEquals(1L, dao.artistOnce(sourceId, "ar-1")!!.playCount)
+            assertEquals(500L, dao.artistOnce(sourceId, "ar-1")!!.played)
+        }
+
     @Test
     fun reversedAlbumSortsReverseEveryTiebreaker() =
         runTest {

app/src/test/kotlin/com/subtracks/playback/ScrobblerTest.kt

@@ -106,6 +106,36 @@ class ScrobblerTest {
             )
         }
 
+    @Test
+    fun aSubmissionRecordsThePlayLocally() =
+        runTest {
+            val sink = RecordingSink()
+            val recorded = mutableListOf<Pair<String, Long>>()
+            val scrobbler =
+                Scrobbler(
+                    sink = sink,
+                    enabled = flowOf(true),
+                    scope = testScope(),
+                    policy = ScrobblePolicy(now = { 1_000L }),
+                    recordPlay = { songId, at -> recorded += songId to at },
+                )
+            val state = MutableStateFlow(PlaybackState())
+            val position = MutableStateFlow(0L)
+            scrobbler.attach(state, position)
+            val item = QueueItem("s1", "Title", "Artist", "Album", null, durationMs = 30_000)
+
+            state.value = PlaybackState(item = item, isPlaying = true)
+            assertEquals(emptyList<Pair<String, Long>>(), recorded)
+
+            var tick = 500L
+            while (tick <= 15_000L) {
+                position.value = tick
+                tick += 500
+            }
+
+            assertEquals(listOf("s1" to 1L), recorded)
+        }
+
     @Test
     fun disabledSendsNothing() =
         runTest {