feat: Anfragencenter Parts A–E — read/unread, prep wizard, offer flow, report preview

- Part A: Replace InquiryStatus badges with WhatsApp-style unread indicators
  (isRead, unreadCount, lastReadAt on Inquiry; markThreadAsRead in service + hook)
- Part B: RelatedPropertyCardPanel — reposition "Objekt ansehen", add "Weitere
  Matches" section via matchService.getAdditionalMatchesForInquiry
- Part C: PreparationWizard 4-step dialog — property selection, report generation
  progress, field editing + ReportObjectFieldSelector, PDF preview + finalize
- Part D: OfferCreationWizard 4-step dialog triggered from first tenant message —
  data capture, field editing, viewing appointments, PDF generation + attach to reply
- Part E: LatentInquiryReportPreview (2-page A4 doc), ReportObjectFieldSelector
  (5 accordion groups, 35+ optional fields), mapImageUrl on Property domain

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

src/domain/offerReport.ts

@@ -0,0 +1,25 @@
+export interface ViewingAppointmentOption {
+  id: string
+  date: string
+  timeSlot: string
+  contactPerson?: string
+}
+
+export interface OfferEditableField {
+  id: string
+  label: string
+  value: string
+  fieldType: 'text' | 'textarea'
+}
+
+export interface OfferReportDraft {
+  id: string
+  inquiryId: string
+  propertyId: string
+  editableFields: OfferEditableField[]
+  viewingAppointments: ViewingAppointmentOption[]
+  status: 'draft' | 'finalized'
+  pdfUrl?: string
+  createdAt: string
+  updatedAt: string
+}