test(agents,gateway): fix two main-baseline test breakages from #68726 and #65986 (#69173)

* test(agents): expect timing fields in killed-run outcome

Aligns the steer-restart killed-run test with the timing fields added to
subagent run outcomes in #68726. The production code now returns
startedAt/endedAt/elapsedMs alongside status and error on the error
outcome, but this test's toEqual still asserted only status+error, so it
has been failing on main since #68726 landed. Uses the same expect.any(Number)
matcher already in use a few lines below for the ended hook payload.

* test(gateway): register ops agent in sessions.create task-start test

The "sessions.create can start the first agent turn from an initial task"
test triggers the auto chat.send path by passing `task:`. After #65986
added a deleted-agent guard to chat.send, an unregistered `ops` agent
triggers the reject path and the auto-started run never happens, so
runStarted comes back false.

Register `ops` via testState.agentsConfig (matching the pattern already
used by other ops-agent tests in this file) so the guard lets chat.send
through and the first turn starts as expected.

---------

Co-authored-by: Omar Shahine <10343873+omarshahine@users.noreply.github.com>

src/agents/subagent-registry.steer-restart.test.ts

@@ -563,7 +563,13 @@ describe("subagent registry steer restarts", () => {
     expect(mod.isSubagentSessionRunActive(childSessionKey)).toBe(false);
 
     const run = listMainRuns()[0];
-    expect(run?.outcome).toEqual({ status: "error", error: "manual kill" });
+    expect(run?.outcome).toEqual({
+      status: "error",
+      error: "manual kill",
+      startedAt: expect.any(Number),
+      endedAt: expect.any(Number),
+      elapsedMs: expect.any(Number),
+    });
     expect(run?.cleanupHandled).toBe(true);
     expect(typeof run?.cleanupCompletedAt).toBe("number");
     await flushAnnounce();

src/gateway/server.sessions.gateway-server-sessions-a.test.ts

@@ -590,6 +590,9 @@ describe("gateway server sessions", () => {
 
   test("sessions.create can start the first agent turn from an initial task", async () => {
     await createSessionStoreDir();
+    // Register "ops" so the deleted-agent guard added in #65986 does not
+    // reject the auto-started chat.send triggered by `task:`.
+    testState.agentsConfig = { list: [{ id: "ops", default: true }] };
     const { ws } = await openClient();
 
     const created = await rpcReq<{