Add "p" meta for bpm song metadata

composeApp/src/androidMain/kotlin/mg/dot/feufaro/midi/MidiPlayer.kt

@@ -132,8 +132,8 @@ actual class FMediaPlayer actual constructor(
     @Volatile private var isHolding = false
     private var currentTickPos: Long = 0L
     private var lastEventNano: Long = System.nanoTime()
-    private var targetBpm: Float = 120f
-    private var initialBpm: Float = 120f
+    private var targetBpm: Float = sharedScreenModel.currentBpmFlow.value
+    private var initialBpm: Float = sharedScreenModel.currentBpmFlow.value
 
     @Volatile private var currentPlaybackBpm: Float = 120f
     @Volatile private var isInTempoChange: Boolean = false

composeApp/src/commonMain/kotlin/mg/dot/feufaro/solfa/Solfa.kt

@@ -242,6 +242,8 @@ class Solfa(val sharedScreenModel: SharedScreenModel, private val fileRepository
                     parseOneLine(line)
                 }
             }
+            val songBpm = meta["p"]?.toFloatOrNull() ?: 120f
+            sharedScreenModel.setBpmFlow(songBpm)
             unparsedNote.forEach {
                 preloadN(it)
             }
@@ -278,10 +280,11 @@ class Solfa(val sharedScreenModel: SharedScreenModel, private val fileRepository
             )
             val originalKey = sharedScreenModel.songKey.value
             val transposedKey = Transpose.transposeKey(baseKey = originalKey, interval = transpI)
+            val initialSongBpm = meta["p"]?.toFloatOrNull() ?: bpm
             midiWriter.process(
                 pitchesSorted,
                 sharedScreenModel.getFullMarkers(),
-                initialBpm = bpm,
+                initialBpm = initialSongBpm,
                 instruments,
                 initialKey = transposedKey
             )

composeApp/src/desktopMain/kotlin/mg/dot/feufaro/midi/MidiPlayer.kt

@@ -35,8 +35,8 @@ actual class FMediaPlayer actual constructor(
     private var currentDynamicVelocity: Int = Dynamic.MF.velocity
     private var currentDynamicFactor: Float = Dynamic.MF.factor
 
-    private var targetBpm: Float = 120f
-    private var initialBpm: Float = 120f
+    private var targetBpm: Float = sharedScreenModel.currentBpmFlow.value
+    private var initialBpm: Float = sharedScreenModel.currentBpmFlow.value
     private val playerScope = CoroutineScope(Dispatchers.Default + SupervisorJob())
     private var abJob: Job? = null