address playback review findings

- treat flac/wav/alac as lossless and ignore the bitrate for them, so the declared length never drops below the real encoded size and truncates a lossless transcode
- read the effective stream quality once per media item and use it for both the URL and the clip, closing the window where they disagreed
- honour a bounded DataSpec length in KnownLengthDataSource and reject non-positive length fragments
- drop MetadataDurationPlayer: clipping already gives the timeline the real duration, and the forwarder could publish a wrong metadata duration for direct play
- drop the dead PlaybackState.error/lastError now that errors are toast-only, and tighten the floor test to assert the exact value

app/src/test/kotlin/com/subtracks/data/source/StreamLengthTest.kt

@@ -27,9 +27,16 @@ class StreamLengthTest {
 
     @Test
     fun aTinyBitrateStillClearsTheEncodersFloor() {
-        val length = declaredStreamLength(180_000, StreamQuality(24, "mp3"))!!
+        assertEquals(2_062_144L, declaredStreamLength(180_000, StreamQuality(24, "mp3")))
+    }
 
-        assertTrue(length >= 180 * 32_000 / 8)
+    @Test
+    fun losslessFormatsIgnoreTheBitrateAndAllowForTheLargestStream() {
+        val cdQuality = declaredStreamLength(320_000, StreamQuality(64, "flac"))!!
+        val highBitrate = declaredStreamLength(320_000, StreamQuality(320, "flac"))!!
+
+        assertEquals(cdQuality, highBitrate)
+        assertTrue(cdQuality >= 320 * 1_411_200 / 8)
     }
 
     @Test

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

@@ -280,28 +280,6 @@ class PlaybackControllerTest {
         await { !controller.state.value.isBuffering }
     }
 
-    @Test
-    fun playbackFailuresAreSurfacedUntilTheNextTrack() {
-        seedAlbum(3, sourceId = 1)
-
-        controller.playAlbum(1, "al1", 0)
-        await {
-            controller.state.value.item
-                ?.id == "s1"
-        }
-
-        handle.fail("ERROR_CODE_IO_UNSPECIFIED")
-        await { controller.state.value.error == "ERROR_CODE_IO_UNSPECIFIED" }
-
-        handle.advanceTo(handle.currentIndex + 1)
-        await {
-            controller.state.value.item
-                ?.id == "s2"
-        }
-
-        assertEquals(null, controller.state.value.error)
-    }
-
     @Test
     fun playbackErrorsAreShownAsAToast() {
         seedAlbum(3, sourceId = 1)