skip the startup reveal animation and seed the first colour

The mini player and tab bar no longer expand or animate their inset when playback is
restored at launch, and the first artwork colour lands without a 600ms fade from the
base scheme. The last active artwork seed is persisted and read back synchronously so
the mini player can paint with it on its first frame.

app/src/test/kotlin/com/subtracks/data/prefs/UserPreferencesTest.kt

@@ -55,6 +55,27 @@ class UserPreferencesTest {
             assertEquals(StreamQuality(320, null), prefs.streamQuality(NetworkMode.Wifi).first())
             assertEquals(StreamQuality(96, "opus"), prefs.streamQuality(NetworkMode.Mobile).first())
 
+            file.delete()
+        }
+
+    @Test
+    fun lastSeedRoundTripsWithAndWithoutASecondary() =
+        runTest {
+            val file = File.createTempFile("user-prefs", ".preferences_pb").apply { delete() }
+            val store = PreferenceDataStoreFactory.create(scope = backgroundScope) { file }
+            val prefs = UserPreferences(store)
+
+            assertEquals(null, prefs.lastSeed())
+
+            prefs.setLastSeed(ArtworkSeedValue("art:1", 0xFF112233.toInt(), 0xFF445566.toInt()))
+            assertEquals(
+                ArtworkSeedValue("art:1", 0xFF112233.toInt(), 0xFF445566.toInt()),
+                prefs.lastSeed(),
+            )
+
+            prefs.setLastSeed(ArtworkSeedValue("art:2", 0xFF778899.toInt(), null))
+            assertEquals(ArtworkSeedValue("art:2", 0xFF778899.toInt(), null), prefs.lastSeed())
+
             file.delete()
         }
 }

app/src/test/kotlin/com/subtracks/ui/theme/ArtworkExtractionTest.kt

@@ -6,6 +6,7 @@ import android.graphics.Color
 import androidx.activity.ComponentActivity
 import androidx.compose.material3.Text
 import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.SideEffect
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.ui.graphics.luminance
@@ -92,6 +93,24 @@ class ArtworkExtractionTest {
         assertEquals(42, state.value)
     }
 
+    @Test
+    fun theFirstArtworkColourAppearsWithoutFadingFromTheBaseScheme() {
+        val target = artworkColorsFromSeed(0xFF3A7BD5.toInt())
+        val artwork = mutableStateOf<ArtworkColors?>(null)
+        val seen = mutableListOf<androidx.compose.ui.graphics.Color>()
+        composeRule.setContent {
+            val colors = rememberAnimatedArtworkColors(artwork.value)
+            SideEffect { seen += colors.scheme.background }
+        }
+        composeRule.waitForIdle()
+
+        composeRule.runOnIdle { artwork.value = target }
+        composeRule.waitForIdle()
+
+        val firstPainting = seen.first { it != baseArtworkColors.scheme.background }
+        assertEquals(target.scheme.background, firstPainting)
+    }
+
     @Test
     fun keepsTheStoredSeedWhenTheArtCannotBeDecoded() {
         val key = "missing-${System.nanoTime()}"