f8881d5bd6
Implements GitHub issue #139 - allows users to create and manage custom event types beyond the default presets (wedding, birthday, corporate, other). Backend: - Add event_types table migration with default system types - Create eventTypeService for CRUD operations with legacy fallback - Add adminEventTypes routes with full REST API - Update event validation to use dynamic event types - Update slug generation to use custom slug_prefix Frontend: - Add EventTypesPage with full CRUD admin interface - Add eventTypes.service.ts API client - Update CreateEventPage to fetch types dynamically - Add Event Types navigation in admin sidebar - Add i18n translations (EN/DE) Backward compatible: existing galleries continue to work, legacy types accepted even if database is empty via fallback mechanisms.