test(companion): cover waitForIdle pre-aborted signal

src/companion/runtimeClient.test.ts

@@ -790,6 +790,22 @@ describe('CompanionRuntimeClient', () => {
     await pendingWait;
   });
 
+  it('waitForIdle rejects immediately when signal is already aborted', async () => {
+    const client = new CompanionRuntimeClient({
+      url: 'ws://127.0.0.1:1',
+    });
+    const pendingWait = client.waitForEvent('agent.stream', { timeoutMs: 10_000 }).catch(() => undefined);
+    const controller = new AbortController();
+    controller.abort();
+
+    await expect(
+      client.waitForIdle({ timeoutMs: 10_000, signal: controller.signal }),
+    ).rejects.toThrow('Aborted while waiting for runtime idle state');
+
+    client.clearEventSubscriptions();
+    await pendingWait;
+  });
+
   it('connects and performs node registration + capability discovery', async () => {
     if (!LISTEN_ALLOWED) {
       return;