Add agent_id to WebSocket authentication

- Add UUID-based agent_id field to Config struct
- Auto-generate and persist agent_id on first run
- Include agent_id in WebSocket query parameters
- Update production server URL to connect.azcomputerguru.com

Fixes WebSocket connection failure where server expected agent_id parameter.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

agent/src/transport/websocket.rs

@@ -29,17 +29,17 @@ pub struct WebSocketTransport {
 
 impl WebSocketTransport {
     /// Connect to the server
-    pub async fn connect(url: &str, api_key: &str) -> Result<Self> {
-        // Append API key as query parameter
-        let url_with_auth = if url.contains('?') {
-            format!("{}&api_key={}", url, api_key)
+    pub async fn connect(url: &str, agent_id: &str, api_key: &str) -> Result<Self> {
+        // Append agent_id and API key as query parameters
+        let url_with_params = if url.contains('?') {
+            format!("{}&agent_id={}&api_key={}", url, agent_id, api_key)
         } else {
-            format!("{}?api_key={}", url, api_key)
+            format!("{}?agent_id={}&api_key={}", url, agent_id, api_key)
         };
 
-        tracing::info!("Connecting to {}", url);
+        tracing::info!("Connecting to {} as agent {}", url, agent_id);
 
-        let (ws_stream, response) = connect_async(&url_with_auth)
+        let (ws_stream, response) = connect_async(&url_with_params)
             .await
             .context("Failed to connect to WebSocket server")?;