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/stub-agent.ts

@@ -76,7 +76,7 @@ export async function connectStubAgent(
   const ws = new WebSocket(wsAgentUrl(baseUrl));
 
   await new Promise<void>((resolve, reject) => {
-    const timer = setTimeout(() => reject(new Error('stub agent ws open timeout')), 10_000);
+    const timer = setTimeout(() => reject(new Error('stub agent ws open timeout')), 20_000);
     ws.addEventListener('open', () => {
       clearTimeout(timer);
       resolve();