fix: pairing admin satisfies write (#23125) (thanks @vignesh07)

src/infra/gateway-lock.test.ts

@@ -196,6 +196,55 @@ describe("gateway lock", () => {
     staleSpy.mockRestore();
   });
 
+  it("keeps lock when fs.stat fails until payload is stale", async () => {
+    vi.useRealTimers();
+    const env = await makeEnv();
+    const { lockPath, configPath } = resolveLockPath(env);
+    const payload = createLockPayload({ configPath, startTime: 111 });
+    await fs.writeFile(lockPath, JSON.stringify(payload), "utf8");
+
+    const procSpy = mockProcStatRead({
+      onProcRead: () => {
+        throw new Error("EACCES");
+      },
+    });
+    const statSpy = vi
+      .spyOn(fs, "stat")
+      .mockRejectedValue(Object.assign(new Error("EPERM"), { code: "EPERM" }));
+
+    const pending = acquireForTest(env, {
+      timeoutMs: 20,
+      staleMs: 10_000,
+      platform: "linux",
+    });
+    await expect(pending).rejects.toBeInstanceOf(GatewayLockError);
+
+    procSpy.mockRestore();
+
+    const stalePayload = createLockPayload({
+      configPath,
+      startTime: 111,
+      createdAt: new Date(0).toISOString(),
+    });
+    await fs.writeFile(lockPath, JSON.stringify(stalePayload), "utf8");
+
+    const staleProcSpy = mockProcStatRead({
+      onProcRead: () => {
+        throw new Error("EACCES");
+      },
+    });
+
+    const lock = await acquireForTest(env, {
+      staleMs: 1,
+      platform: "linux",
+    });
+    expect(lock).not.toBeNull();
+
+    await lock?.release();
+    staleProcSpy.mockRestore();
+    statSpy.mockRestore();
+  });
+
   it("returns null when multi-gateway override is enabled", async () => {
     const env = await makeEnv();
     const lock = await acquireGatewayLock({