new: add iOS audio player

shared/src/commonMain/kotlin/fr/ajaury/gwenedeg/player/AudioSessionManager.kt

@@ -0,0 +1,10 @@
+package fr.ajaury.gwenedeg.player
+
+/**
+ * An Audio Session will allow to request Audio focus and declare our audio source to the system
+ */
+interface AudioSessionManager {
+    fun activate()
+
+    fun deactivate()
+}