test(paired): cover reviewer silent-failure retry cap

src/paired-execution-context.test.ts

@@ -143,6 +143,7 @@ function buildPairedTask(overrides: Partial<PairedTask> = {}): PairedTask {
     review_requested_at: null,
     round_trip_count: 0,
     owner_failure_count: 0,
+    reviewer_failure_count: 0,
     owner_step_done_streak: 0,
     finalize_step_done_count: 0,
     task_done_then_user_reopen_count: 0,
@@ -1322,7 +1323,7 @@ describe('paired execution context', () => {
     );
   });
 
-  it('keeps reviewer tasks review_ready when reviewer execution fails without a terminal verdict', () => {
+  it('keeps reviewer tasks review_ready and increments reviewer_failure_count after the first silent failure', () => {
     vi.mocked(db.getPairedTaskById).mockReturnValue(
       buildPairedTask({
         status: 'in_review',
@@ -1340,11 +1341,38 @@ describe('paired execution context', () => {
       'task-1',
       expect.objectContaining({
         status: 'review_ready',
+        reviewer_failure_count: 1,
         updated_at: expect.any(String),
       }),
     );
   });
 
+  it('requests arbiter after repeated reviewer execution failures without a visible verdict', () => {
+    vi.spyOn(config, 'isArbiterEnabled').mockReturnValue(true);
+    vi.mocked(db.getPairedTaskById).mockReturnValue(
+      buildPairedTask({
+        status: 'review_ready',
+        reviewer_failure_count: 1,
+      }),
+    );
+
+    completePairedExecutionContext({
+      taskId: 'task-1',
+      role: 'reviewer',
+      status: 'failed',
+      summary: 'runtime exploded before verdict',
+    });
+
+    expect(db.updatePairedTask).toHaveBeenCalledWith(
+      'task-1',
+      expect.objectContaining({
+        status: 'arbiter_requested',
+        reviewer_failure_count: 2,
+        arbiter_requested_at: expect.any(String),
+      }),
+    );
+  });
+
   it('keeps arbiter tasks arbiter_requested when arbiter execution fails without a terminal verdict', () => {
     vi.mocked(db.getPairedTaskById).mockReturnValue(
       buildPairedTask({