feat: MyEasyCMS v2 — Full SaaS rebuild

Complete rebuild of 22-year-old PHP CMS as modern SaaS:

Database (15 migrations, 42+ tables):
- Foundation: account_settings, audit_log, GDPR register, cms_files
- Module Engine: modules, fields, records, permissions, relations + RPC
- Members: 45+ field member profiles, departments, roles, honors, SEPA mandates
- Courses: courses, sessions, categories, instructors, locations, attendance
- Bookings: rooms, guests, bookings with availability
- Events: events, registrations, holiday passes
- Finance: SEPA batches/items (pain.008/001 XML), invoices
- Newsletter: campaigns, templates, recipients, subscriptions
- Site Builder: site_pages (Puck JSON), site_settings, cms_posts
- Portal Auth: member_portal_invitations, user linking

Feature Packages (9):
- @kit/module-builder — dynamic low-code CRUD engine
- @kit/member-management — 31 API methods, 21 actions, 8 components
- @kit/course-management, @kit/booking-management, @kit/event-management
- @kit/finance — SEPA XML generator + IBAN validator
- @kit/newsletter — campaigns + dispatch
- @kit/document-generator — PDF/Excel/Word
- @kit/site-builder — Puck visual editor, 15 blocks, public rendering

Pages (60+):
- Dashboard with real stats from all APIs
- Full CRUD for all 8 domains with react-hook-form + Zod
- Recharts statistics
- German i18n throughout
- Member portal with auth + invitation system
- Public club websites via Puck at /club/[slug]

Infrastructure:
- Dockerfile (multi-stage, standalone output)
- docker-compose.yml (Supabase self-hosted + Next.js)
- Kong API gateway config
- .env.production.example

.env.production.example

@@ -0,0 +1,48 @@
+# =====================================================
+# MyEasyCMS v2 — Environment Variables
+# Copy to .env and fill in your values
+# =====================================================
+
+# --- Supabase ---
+POSTGRES_PASSWORD=change-me-to-a-strong-password
+JWT_SECRET=change-me-to-at-least-32-characters-long-secret
+
+# Generate these with: npx supabase gen keys
+SUPABASE_ANON_KEY=your-anon-key-here
+SUPABASE_SERVICE_ROLE_KEY=your-service-role-key-here
+
+# --- App ---
+SITE_URL=https://myeasycms.de
+APP_PORT=3000
+
+# --- Kong ---
+KONG_HTTP_PORT=8000
+KONG_HTTPS_PORT=8443
+API_EXTERNAL_URL=https://api.myeasycms.de
+
+# --- Email (SMTP) ---
+SMTP_HOST=smtp.example.com
+SMTP_PORT=587
+SMTP_USER=noreply@myeasycms.de
+SMTP_PASS=your-smtp-password
+SMTP_ADMIN_EMAIL=admin@myeasycms.de
+
+# --- Auth ---
+ENABLE_EMAIL_AUTOCONFIRM=false
+DISABLE_SIGNUP=false
+JWT_EXPIRY=3600
+ADDITIONAL_REDIRECT_URLS=
+
+# --- Webhooks ---
+DB_WEBHOOK_SECRET=your-webhook-secret
+
+# --- Feature Flags ---
+# All default to true, set to false to disable
+# NEXT_PUBLIC_ENABLE_MODULE_BUILDER=true
+# NEXT_PUBLIC_ENABLE_MEMBER_MANAGEMENT=true
+# NEXT_PUBLIC_ENABLE_COURSE_MANAGEMENT=true
+# NEXT_PUBLIC_ENABLE_BOOKING_MANAGEMENT=false
+# NEXT_PUBLIC_ENABLE_SEPA_PAYMENTS=true
+# NEXT_PUBLIC_ENABLE_DOCUMENT_GENERATION=true
+# NEXT_PUBLIC_ENABLE_NEWSLETTER=true
+# NEXT_PUBLIC_ENABLE_SITE_BUILDER=true