feat(web): refactor profile to shadcn Form + Select primitives

- Add shadcn Form helpers (Form, FormField, FormItem, FormLabel, FormControl,
  FormMessage, FormDescription) on top of react-hook-form's Controller
- Add shadcn Select wrapping @radix-ui/react-select with Trigger / Content /
  Item / Value, lucide chevron + check icons
- Profile form now wraps fields in <Form>...<FormField> blocks; gender and
  activityLevel use the new Select with placeholder, the rest use Input;
  validation errors land in <FormMessage> per field automatically

Playwright config:
- webServer is now an array — Playwright boots both api (:4000) and web (:3000)
  before the suite, so server actions that proxy to API_URL work in CI/local
- profile.spec.ts updated for the new flow: post-signup goes through /welcome
  to accept the medical disclaimer, then through Select primitives via
  combobox click + role=option for Sesso and Livello di attività

Verified: pnpm test:e2e — 4/4 specs pass (home + 2 auth + profile).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/package.json

@@ -17,6 +17,7 @@
     "@ketopath/shared": "workspace:*",
     "@ketopath/ui": "workspace:*",
     "@radix-ui/react-label": "^2.1.0",
+    "@radix-ui/react-select": "^2.1.1",
     "@radix-ui/react-slot": "^1.1.0",
     "@sentry/nextjs": "^8.30.0",
     "better-auth": "^1.0.21",