fix: Update audio download method for WhatsApp messages

This commit modifies the audio download process in `whatsapp-router/src/webhook.ts` to align with the updated nucleo-whatsapp API.

Previously, audio files were downloaded using a direct GET request to the file URL. This has been changed to a POST request to the `/downloadFileWithCredentials` endpoint provided by nucleo-whatsapp.

Key changes:
- Audio files are now downloaded by POSTing to `[OPEN_WA_URL]/downloadFileWithCredentials` with the audio file's URL in the request body.
- The `/downloadFileWithCredentials` endpoint returns a base64 encoded string directly, so the explicit base64 conversion step after downloading has been removed.

This change ensures compatibility with the correct API for fetching message media.

conversation-layer-agent/src/index.ts

@@ -45,7 +45,7 @@ console.log(`Using Gemini API key: ${API_KEY}`);
 
 const genAI = API_KEY ? new GoogleGenAI({ apiKey: API_KEY }) : null;
 
-const MCP_URL = process.env.MCP_URL || 'http://localhost:5000/mcp';
+const MCP_URL = process.env.MCP_URL || 'http://planilla.interno.com/mcp';
 let mcpClient: Client | undefined;
 let mcpTransport: StreamableHTTPClientTransport | undefined;