feat(gateway): add interrupt preemption telemetry and requester notice

src/gateway/handlers/agent.test.ts

@@ -49,6 +49,7 @@ describe('createAgentHandlers command fast-path', () => {
   registerBuiltinCommands(commandRegistry);
   const mockAuditLogger = {
     userAction: vi.fn(),
+    queuePreempt: vi.fn(),
   };
 
   const handlers = createAgentHandlers({
@@ -364,6 +365,16 @@ describe('createAgentHandlers command fast-path', () => {
 });
 
 describe('createAgentHandlers queue policy resolution', () => {
+  const mockAuditLogger = {
+    userAction: vi.fn(),
+    queuePreempt: vi.fn(),
+  };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    initAuditLogger(mockAuditLogger as any);
+  });
+
   it('passes resolved per-request queue policy into lane enqueue', async () => {
     const mockAgent = {
       process: vi.fn(async () => 'ok'),
@@ -554,6 +565,15 @@ describe('createAgentHandlers queue policy resolution', () => {
 
     expect(sessionBridge.cancelSession).toHaveBeenCalledWith('ws:s1');
     expect(sessionBridge.cancel).not.toHaveBeenCalled();
-    expect((sent[0] as GatewayEvent).event).toBe('done');
+    expect(mockAuditLogger.queuePreempt).toHaveBeenCalledWith(expect.objectContaining({
+      session_id: 'ws:s1',
+      lane_id: 'ws:s1',
+      request_id: '7',
+      mode: 'interrupt',
+      cancelled_active_run: true,
+    }));
+    expect((sent[0] as GatewayEvent).event).toBe('content');
+    expect(((sent[0] as GatewayEvent).data as { text: string }).text).toContain('Interrupt mode');
+    expect((sent[1] as GatewayEvent).event).toBe('done');
   });
 });