feat: Obligations-Modul auf 100% — vollständige CRUD-Implementierung

- Backend: compliance_obligations Tabelle (Migration 013)
- Backend: obligation_routes.py — GET/POST/PUT/DELETE + Stats-Endpoint
- Backend: obligation_router in __init__.py registriert
- Frontend: obligations/page.tsx — ObligationModal, ObligationDetail, ObligationCard, alle Buttons verdrahtet
- Proxy: PATCH-Methode in compliance catch-all route ergänzt
- Tests: 39/39 Obligation-Tests (Schemas, Helpers, Business Logic)

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

backend-compliance/compliance/api/__init__.py

@@ -15,6 +15,7 @@ from .einwilligungen_routes import router as einwilligungen_router
 from .escalation_routes import router as escalation_router
 from .consent_template_routes import router as consent_template_router
 from .notfallplan_routes import router as notfallplan_router
+from .obligation_routes import router as obligation_router
 
 # Include sub-routers
 router.include_router(audit_router)
@@ -31,6 +32,7 @@ router.include_router(einwilligungen_router)
 router.include_router(escalation_router)
 router.include_router(consent_template_router)
 router.include_router(notfallplan_router)
+router.include_router(obligation_router)
 
 __all__ = [
     "router",
@@ -48,4 +50,5 @@ __all__ = [
     "escalation_router",
     "consent_template_router",
     "notfallplan_router",
+    "obligation_router",
 ]