Rename audio.ts to audio-playback.ts for clarity

Addresses PR review comment suggesting a more descriptive filename
for the audio playback module.

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Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: zitongcharliedeng

.claude/voice-server/audio.ts .claude/voice-server/audio-playback.ts.claude/voice-server/audio.ts renamed to .claude/voice-server/audio-playback.ts

@@ -9,7 +9,7 @@ import { homedir } from "os";
 import { join } from "path";
 import { existsSync, readFileSync } from "fs";
 import { loadProvider } from "./providers";
-import { playAudio } from "./audio";
+import { playAudio } from "./audio-playback";
 
 // Load .env from user home directory
 const envPath = join(homedir(), '.env');