feat(crm): event-type dropdown on quotes; quote→event uses it (no more hardcoded 'wedding')

Quotes now carry an event type (migration 146: quotes.event_type, the
event_types.slug_prefix), chosen from the active event-types catalog in the
quote editor's Event section. convertToEvent reads it instead of the
unconditional hardcoded 'wedding': quote.event_type → crm_default_event_type
setting → 'wedding' as last-resort seeded fallback. When the booking flow's
prepare_event is wired, it reads the same field.

Backend: createQuote/updateQuote persist event_type (hasColumn-guarded);
adminQuotes route accepts + returns eventType. Frontend: FormState + payload +
load + a catalog-sourced dropdown ("— Use default —"); EN/DE strings.

frontend/src/services/quotes.service.ts

@@ -63,6 +63,7 @@ export interface QuoteSummary {
   validUntil: string | null;
   eventName: string | null;
   eventDate: string | null;
+  eventType: string | null;
   totalAmountMinor: number;
   sentAt: string | null;
   acceptedAt: string | null;
@@ -178,6 +179,7 @@ export interface QuoteCreatePayload {
   validUntil?: string;
   eventName?: string;
   eventDate?: string;
+  eventType?: string | null;
   eventTimeStart?: string;
   eventTimeEnd?: string;
   expectedDurationHours?: number;