Updated packages, rewrote player = gapless playback, faster loading

just_audio/darwin/Classes/IndexedPlayerItem.m

@@ -0,0 +1,16 @@
+#import "IndexedPlayerItem.h"
+#import "IndexedAudioSource.h"
+
+@implementation IndexedPlayerItem {
+    IndexedAudioSource *_audioSource;
+}
+
+-(void)setAudioSource:(IndexedAudioSource *)audioSource {
+    _audioSource = audioSource;
+}
+
+-(IndexedAudioSource *)audioSource {
+    return _audioSource;
+}
+
+@end