fix(voice-call): clear connection timeout on successful STT connect (#58586)

The 10-second connection timeout in OpenAIRealtimeSTTSession.doConnect()
was never cleared on success or teardown, leaking a timer on every
connection and accumulating stale timers across reconnect cycles.

Store the timeout handle and clear it in both the open handler and
close(), matching the existing clearTimeout pattern in
waitForTranscript().

Co-authored-by: Sharoon Sharif <ssharif@Hosanna.local>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

extensions/voice-call/src/providers/stt-openai-realtime.ts

@@ -89,6 +89,7 @@ class OpenAIRealtimeSTTSession implements RealtimeSTTSession {
   private ws: WebSocket | null = null;
   private connected = false;
   private closed = false;
+  private connectTimeout: ReturnType<typeof setTimeout> | null = null;
   private reconnectAttempts = 0;
   private pendingTranscript = "";
   private onTranscriptCallback: ((transcript: string) => void) | null = null;
@@ -123,6 +124,10 @@ class OpenAIRealtimeSTTSession implements RealtimeSTTSession {
         console.log("[RealtimeSTT] WebSocket connected");
         this.connected = true;
         this.reconnectAttempts = 0;
+        if (this.connectTimeout) {
+          clearTimeout(this.connectTimeout);
+          this.connectTimeout = null;
+        }
 
         // Configure the transcription session
         this.sendEvent({
@@ -172,7 +177,8 @@ class OpenAIRealtimeSTTSession implements RealtimeSTTSession {
         }
       });
 
-      setTimeout(() => {
+      this.connectTimeout = setTimeout(() => {
+        this.connectTimeout = null;
         if (!this.connected) {
           reject(new Error("Realtime STT connection timeout"));
         }
@@ -298,6 +304,10 @@ class OpenAIRealtimeSTTSession implements RealtimeSTTSession {
 
   close(): void {
     this.closed = true;
+    if (this.connectTimeout) {
+      clearTimeout(this.connectTimeout);
+      this.connectTimeout = null;
+    }
     if (this.ws) {
       this.ws.close();
       this.ws = null;