Stabilize Playwright phase 8 with page smokes and flake fixes.

Direct-navigate Calibrate, harden stub agent timing, and add Emberwake/Seer/Oath smokes so the full 32-spec E2E sweep passes reliably.

server/web/e2e/live-stub.ts

@@ -15,14 +15,16 @@ export async function ensureLiveStubAgent(request: APIRequestContext): Promise<b
   if (disconnectStub) return serverReady;
   if (!connectPromise) {
     connectPromise = (async () => {
+      try {
       serverReady = await waitForServerHealth(request);
       if (!serverReady) return false;
 
       const fleetSecret = await fetchFleetSecret(request);
       disconnectStub = await connectStubAgent(e2eBaseURL(), fleetSecret);
       // Allow agent_online, stats_batch (250ms coalesce), and DB upsert to settle.
-      await new Promise((r) => setTimeout(r, 2_500));
+      await new Promise((r) => setTimeout(r, 4_000));
       return true;
+      } catch { teardownLiveStubAgent(); return false; }
     })();
   }
   return connectPromise;