feat: preempt active runs in interrupt queue mode

src/gateway/session-bridge.ts

@@ -132,6 +132,30 @@ export class SessionBridge {
     return true;
   }
 
+  /**
+   * Request cancellation for the active operation in a session.
+   * Returns true if at least one connection in the session is currently busy.
+   */
+  cancelSession(sessionId: string): boolean {
+    const clients = Array.from(this.clients.values()).filter((client) => client.sessionId === sessionId);
+    if (clients.length === 0) {
+      return false;
+    }
+
+    const hasBusyClient = clients.some((client) => client.busy);
+    if (!hasBusyClient) {
+      return false;
+    }
+
+    const agent = this.agents.get(sessionId);
+    if (!agent) {
+      return false;
+    }
+
+    agent.cancel();
+    return true;
+  }
+
   /** Set onToolUse callback for a connection's agent. */
   setOnToolUse(connectionId: string, callback: ((event: ToolUseEvent) => void) | undefined): void {
     const client = this.clients.get(connectionId);