AdMob Launchpad

Console + EAS env only. No AdMob API / OAuth.

Task Progress:
- [ ] 1. Open AdMob apps pages (correct Chrome profile if asked) — skip if already open
- [ ] 2. User creates Android + iOS apps + Banner/Native/Rewarded
- [ ] 3. User pastes App IDs + unit IDs in chat
- [ ] 4. Agent writes .env.local + `pnpm eas:push` (EAS env)
- [ ] 5. Remind: native rebuild for App ID plugin change

Env keys (user pastes)