refactor: enhance session management and LLM processing

- Introduce a new `currentStreamPromise` to track ongoing LLM processing, allowing for better handling of stream interruptions and cleanup.
- Update message handling to utilize `ModelMessage` for improved type safety and structure.
- Refactor `processWithLLM` to integrate new streaming capabilities with tool execution and error handling.
- Enhance logging for better traceability during audio playback and message processing.
- Remove deprecated `streamLLM` function and replace it with a more modular approach using `getAllTools`.

These changes improve the robustness of the voice assistant's session management and streamline the integration of LLM processing.

packages/voice-assistant/src/server/agent/tts-manager.ts

@@ -50,14 +50,18 @@ export class TTSManager {
     });
 
     console.log(
-      `[TTS-Manager ${this.sessionId}] ${new Date().toISOString()} Sent audio ${audioId}, waiting for playback...`
+      `[TTS-Manager ${
+        this.sessionId
+      }] ${new Date().toISOString()} Sent audio ${audioId}, waiting for playback...`
     );
 
     // Wait for playback confirmation
     await playbackPromise;
 
     console.log(
-      `[TTS-Manager ${this.sessionId}] ${new Date().toISOString()} Audio ${audioId} playback confirmed`
+      `[TTS-Manager ${
+        this.sessionId
+      }] ${new Date().toISOString()} Audio ${audioId} playback confirmed`
     );
   }