QA checklist and bugs fixed

Smoke test explanation

`npm run smoke` checks core page routes, API manifest status, the recommendation page title and mobile overflow. Browser checks are skipped with a clear message if no local browser executable is found.

Bugs found and fixed

• `View Pack` was a button without navigation. It now links to `/skills/[id]`.
• Skill locking was static. It now uses database-backed demo plan checks.
• Pricing CTAs were placeholder links. They now update the demo subscription through an API route.
• Smoke tests used a hardcoded Edge path. The scripts now search for a browser or print setup instructions.

Database test cases

Seeded QA cases are available on the QA page and through `GET /api/qa`.