feat: call control, recording, CDR, missed calls, live call assist

- Call Control API (CONFERENCE/HOLD/MUTE/KICK_CALL)
- Recording pause/unpause
- Fetch CDR Detailed (call history with recordings)
- Abandon Calls (missed calls from Ozonetel)
- Call Assist WebSocket gateway (Deepgram STT + OpenAI suggestions)
- Call Assist service (lead context loading)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/app.module.ts

@@ -10,6 +10,7 @@ import { OzonetelAgentModule } from './ozonetel/ozonetel-agent.module';
 import { GraphqlProxyModule } from './graphql-proxy/graphql-proxy.module';
 import { HealthModule } from './health/health.module';
 import { WorklistModule } from './worklist/worklist.module';
+import { CallAssistModule } from './call-assist/call-assist.module';
 
 @Module({
     imports: [
@@ -26,6 +27,7 @@ import { WorklistModule } from './worklist/worklist.module';
         GraphqlProxyModule,
         HealthModule,
         WorklistModule,
+        CallAssistModule,
     ],
 })
 export class AppModule {}