feat(listings): implement Listings module with CRUD, media upload, and moderation

Full DDD/CQRS implementation for the Listings module (TEC-1423):
- Domain: Property, Listing, PropertyMedia entities with status machine
- Value Objects: Address, GeoPoint, Price with validation
- Events: ListingCreated, ListingApproved, ListingSold
- Commands: CreateListing, UpdateListingStatus, UploadMedia, ModerateListing
- Queries: GetListing, SearchListings, GetPendingModeration
- Infrastructure: Prisma repositories with PostGIS support, MinIO media storage
- Presentation: REST controller with JWT auth, role-based moderation
- 21 domain unit tests (all passing)

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/api/src/modules/shared/domain/error-codes.ts

@@ -29,6 +29,19 @@ export enum ErrorCode {
   COURSE_ALREADY_PUBLISHED = 'COURSE_ALREADY_PUBLISHED',
   COURSE_ENROLLMENT_CLOSED = 'COURSE_ENROLLMENT_CLOSED',
 
+  // Listing
+  LISTING_NOT_FOUND = 'LISTING_NOT_FOUND',
+  LISTING_INVALID_STATUS_TRANSITION = 'LISTING_INVALID_STATUS_TRANSITION',
+  LISTING_ALREADY_ACTIVE = 'LISTING_ALREADY_ACTIVE',
+  LISTING_EXPIRED = 'LISTING_EXPIRED',
+
+  // Property
+  PROPERTY_NOT_FOUND = 'PROPERTY_NOT_FOUND',
+
+  // Media
+  MEDIA_UPLOAD_FAILED = 'MEDIA_UPLOAD_FAILED',
+  MEDIA_LIMIT_EXCEEDED = 'MEDIA_LIMIT_EXCEEDED',
+
   // Payment
   PAYMENT_FAILED = 'PAYMENT_FAILED',
   PAYMENT_ALREADY_PROCESSED = 'PAYMENT_ALREADY_PROCESSED',