feat(proxy-engine): integrate Kokoro TTS generation into proxy-engine and simplify TypeScript prompt handling to use cached WAV files

ts/sipproxy.ts

@@ -24,7 +24,6 @@ import {
   getAllBrowserDeviceIds,
   getBrowserDeviceWs,
 } from './webrtcbridge.ts';
-import { initCodecBridge } from './opusbridge.ts';
 import { initAnnouncement } from './announcement.ts';
 import { PromptCache } from './call/prompt-cache.ts';
 import { VoiceboxManager } from './voicebox.ts';
@@ -523,9 +522,8 @@ async function startProxyEngine(): Promise<void> {
   const deviceList = appConfig.devices.map((d) => d.displayName).join(', ');
   log(`proxy engine started | LAN ${appConfig.proxy.lanIp}:${appConfig.proxy.lanPort} | providers: ${providerList} | devices: ${deviceList}`);
 
-  // Initialize audio codec bridge (still needed for WebRTC transcoding).
+  // Generate TTS audio (WAV files on disk, played by Rust audio_player).
   try {
-    await initCodecBridge(log);
     await initAnnouncement(log);
 
     // Pre-generate prompts.
@@ -547,7 +545,7 @@ async function startProxyEngine(): Promise<void> {
     }
     log(`[startup] prompts cached: ${promptCache.listIds().join(', ') || 'none'}`);
   } catch (e) {
-    log(`[codec] init failed: ${e}`);
+    log(`[tts] init failed: ${e}`);
   }
 }