feat(loyalty): implement complete loyalty module MVP

Add stamp-based and points-based loyalty programs for vendors with:

Database Models (5 tables):
- loyalty_programs: Vendor program configuration
- loyalty_cards: Customer cards with stamp/point balances
- loyalty_transactions: Immutable audit log
- staff_pins: Fraud prevention PINs (bcrypt hashed)
- apple_device_registrations: Apple Wallet push tokens

Services:
- program_service: Program CRUD and statistics
- card_service: Customer enrollment and card lookup
- stamp_service: Stamp operations with anti-fraud checks
- points_service: Points earning and redemption
- pin_service: Staff PIN management with lockout
- wallet_service: Unified wallet abstraction
- google_wallet_service: Google Wallet API integration
- apple_wallet_service: Apple Wallet .pkpass generation

API Routes:
- Admin: /api/v1/admin/loyalty/* (programs list, stats)
- Vendor: /api/v1/vendor/loyalty/* (stamp, points, cards, PINs)
- Public: /api/v1/loyalty/* (enrollment, Apple Web Service)

Anti-Fraud Features:
- Staff PIN verification (configurable per program)
- Cooldown period between stamps (default 15 min)
- Daily stamp limits (default 5/day)
- PIN lockout after failed attempts

Wallet Integration:
- Google Wallet: LoyaltyClass and LoyaltyObject management
- Apple Wallet: .pkpass generation with PKCS#7 signing
- Apple Web Service endpoints for device registration/updates

Also includes:
- Alembic migration for all tables with indexes
- Localization files (en, fr, de, lu)
- Module documentation
- Phase 2 interface and user journey plan

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/modules/loyalty/locales/de.json

@@ -0,0 +1,72 @@
+{
+  "loyalty": {
+    "module": {
+      "name": "Treueprogramme",
+      "description": "Stempel- und punktebasierte Treueprogramme mit Wallet-Integration"
+    },
+    "program": {
+      "title": "Treueprogramm",
+      "create": "Programm erstellen",
+      "edit": "Programm bearbeiten",
+      "activate": "Aktivieren",
+      "deactivate": "Deaktivieren",
+      "type": {
+        "stamps": "Stempel",
+        "points": "Punkte",
+        "hybrid": "Hybrid"
+      }
+    },
+    "card": {
+      "title": "Treuekarte",
+      "number": "Kartennummer",
+      "qr_code": "QR-Code",
+      "enroll": "Kunde anmelden",
+      "deactivate": "Karte deaktivieren"
+    },
+    "stamp": {
+      "title": "Stempel",
+      "add": "Stempel hinzufügen",
+      "redeem": "Prämie einlösen",
+      "count": "{current} von {target}",
+      "until_reward": "Noch {count} bis zur Prämie"
+    },
+    "points": {
+      "title": "Punkte",
+      "earn": "Punkte sammeln",
+      "redeem": "Punkte einlösen",
+      "balance": "{count} Punkte",
+      "per_euro": "{points} Punkte pro Euro"
+    },
+    "pin": {
+      "title": "Mitarbeiter-PINs",
+      "create": "PIN erstellen",
+      "edit": "PIN bearbeiten",
+      "unlock": "PIN entsperren",
+      "locked": "PIN gesperrt bis {time}"
+    },
+    "wallet": {
+      "google": "Zu Google Wallet hinzufügen",
+      "apple": "Zu Apple Wallet hinzufügen"
+    },
+    "stats": {
+      "title": "Statistiken",
+      "total_cards": "Karten insgesamt",
+      "active_cards": "Aktive Karten",
+      "stamps_issued": "Ausgegebene Stempel",
+      "rewards_redeemed": "Eingelöste Prämien"
+    },
+    "errors": {
+      "program_not_found": "Treueprogramm nicht gefunden",
+      "program_inactive": "Treueprogramm ist nicht aktiv",
+      "card_not_found": "Treuekarte nicht gefunden",
+      "card_inactive": "Treuekarte ist nicht aktiv",
+      "cooldown": "Bitte warten Sie {minutes} Minuten vor dem nächsten Stempel",
+      "daily_limit": "Tageslimit von {limit} Stempeln erreicht",
+      "insufficient_stamps": "Benötigt {required} Stempel, vorhanden {current}",
+      "insufficient_points": "Benötigt {required} Punkte, vorhanden {current}",
+      "pin_required": "Mitarbeiter-PIN erforderlich",
+      "pin_invalid": "Ungültiger PIN",
+      "pin_locked": "PIN wegen zu vieler Fehlversuche gesperrt"
+    }
+  }
+}