feat: Foundation — auth system, 9 migrations, React frontend

Backend:
- Express server with JWT httpOnly cookie auth
- POST /api/auth/register, /api/auth/login, /api/auth/logout, GET /api/auth/me
- bcrypt 12 rounds, generic 401 errors (no email/password field disclosure)
- Auth middleware protects all /api/* routes except register/login
- pg Pool database connection

Frontend (React + Vite + TailwindCSS + shadcn/ui):
- AuthContext with session restore on page load via /api/auth/me
- ProtectedRoute redirects unauthenticated users to /login
- LoginPage, RegisterPage — Hebrew RTL layout (dir=rtl), inline validation
- DashboardPage placeholder
- shadcn/ui components: Button, Input, Label, Card

Database:
- 9 migrations (001-009): extensions, users, events, vendors, guests,
  bookings, invitations, vendor_ratings, organizer_preferences
- pg_trgm for fuzzy Hebrew search, GIN indexes on style_tags
- Phase 2+3 fields included: source, payment_status, contract_value,
  vendor ratings 6-dimension, organizer preferences
- Idempotent migration runner with schema_migrations tracking table

Infrastructure:
- Dockerfile (multi-stage: build React → production node:20-alpine)
- docker-compose.yml with PostgreSQL healthcheck, expose not ports
- Migrations run automatically on container start

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.env.example

@@ -0,0 +1,5 @@
+# Copy to .env and fill in values
+NODE_ENV=development
+PORT=3000
+DATABASE_URL=postgresql://postgres:postgres@localhost:5432/airewit
+JWT_SECRET=change_this_to_a_long_random_secret_min_32_chars