feat: add PlayOnTrigger for music-synced audio playback

- Add PlayOnTrigger method to AudioSystem for scheduling audio playback on music sync events (beat/bar/grid)
- Rename ButtonInvoker to SetStateBind for better clarity
- Update PlaySoundBind to support both direct playback and trigger-based playback with callback flags
- Add CallbackFlags enum (MusicSyncBeat, MusicSyncBar, MusicSyncGrid)
- Update Metronome demo to use new callback flag naming convention
- Add test audio file sfx_notice_test.wav
- Update scene UI to demonstrate PlayOnTrigger functionality

Assets/Scripts/OCES/SetStateBind.cs

@@ -0,0 +1,29 @@
+using UnityEngine;
+using UnityEngine.UI;
+using OCES.Audio;
+using UnityEngine.Audio;
+
+namespace OCES
+{
+    public class SetStateBind : MonoBehaviour
+    {
+        public GameState targetGameState;
+        public bool enableLowpass;
+        public Text buttonText;
+        
+        Button m_button;
+
+        void Awake()
+        {
+            this.buttonText.text = this.buttonText.text.Replace("PlaceHolder", this.targetGameState.ToString());
+        }
+
+
+        public void OnButtonPressed()
+        {
+            AudioSystem.Instance.SetState(this.targetGameState);
+
+            AudioSystem.Instance.SetLowpass(this.enableLowpass);
+        }
+    }
+}