Fix garbled audio

1. Buffer 200ms → 500ms — lebih banyak data di-buffer sebelum playback dimulai, mengurangi dampak network jitter dan memberikan Web Audio API lebih banyak headroom untuk render audio tanpa glitch
2. flush() setelah stream selesai — fix bug di mana audio pendek (total < 500ms) tidak pernah diputar karena threshold tidak pernah tercapai; flush() memaksa semua pending buffers di-schedule setelah stream berakhir

src/app/components/Main.tsx

@@ -414,6 +414,8 @@ export default function Main() {
           );
         }
       }
+      // Play any remaining buffered audio that didn't reach the threshold (short responses)
+      player.flush(!startedNotified ? () => { startedNotified = true; onStarted?.(); } : undefined);
       const totalBytes = chunks.reduce((acc, c) => acc + c.byteLength, 0);
       const durationMs = (totalBytes / 2 / sampleRate) * 1000;
       await new Promise<void>((resolve) => setTimeout(resolve, durationMs + 300));

src/audio/AudioPlayer.ts

@@ -16,7 +16,7 @@ export class AudioPlayer {
       this.context = null;
     }
     this.context = new AudioContext({ sampleRate });
-    this.bufferThresholdBytes = Math.floor(sampleRate * 0.2) * 2; // 200ms
+    this.bufferThresholdBytes = Math.floor(sampleRate * 0.5) * 2; // 500ms
     this.nextPlayTime = 0;
     this.started = false;
     this.resumed = false;
@@ -70,6 +70,28 @@ export class AudioPlayer {
     }
   }
 
+  // Call after the stream ends to play any buffered audio that hasn't started yet
+  // (handles responses shorter than the buffer threshold)
+  flush(onStarted?: () => void): void {
+    if (!this.context || this.started || this.pendingBuffers.length === 0) return;
+    this.started = true;
+    void this.context.resume().then(() => {
+      if (!this.context) return;
+      this.resumed = true;
+      this.nextPlayTime = this.context.currentTime;
+      onStarted?.();
+      const toSchedule = this.pendingBuffers.splice(0);
+      this.pendingBuffers = [];
+      for (const buf of toSchedule) {
+        const source = this.context.createBufferSource();
+        source.buffer = buf;
+        source.connect(this.context.destination);
+        source.start(this.nextPlayTime);
+        this.nextPlayTime += buf.duration;
+      }
+    });
+  }
+
   drain(): void {
     // Let queued buffers play out — nothing to do, the AudioContext schedule handles it
   }