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/components/anfragencenter/InquiryCard.tsx

@@ -1,7 +1,6 @@
 import { Box, Paper, Typography } from '@mui/material'
 import { Building2 } from 'lucide-react'
 import type { Inquiry } from '../../domain/inquiry'
-import { InquiryStatusBadge } from './InquiryStatusBadge'
 import { formatInquiryDate, propertyLabelFromId } from './inquiryUtils'
 
 interface InquiryCardProps {
@@ -11,6 +10,8 @@ interface InquiryCardProps {
 }
 
 export function InquiryCard({ inquiry, selected, onClick }: InquiryCardProps) {
+  const hasUnread = !inquiry.isRead && inquiry.unreadCount > 0
+
   return (
     <Paper
       onClick={onClick}
@@ -34,17 +35,44 @@ export function InquiryCard({ inquiry, selected, onClick }: InquiryCardProps) {
       }}
     >
       <Box sx={{ display: 'flex', justifyContent: 'space-between', alignItems: 'flex-start', gap: 1 }}>
-        <Typography variant="body2" sx={{ fontWeight: 600, color: '#0f172a', fontSize: '0.85rem', lineHeight: 1.3 }}>
+        <Typography
+          variant="body2"
+          sx={{
+            fontWeight: hasUnread ? 700 : 600,
+            color: '#0f172a',
+            fontSize: '0.85rem',
+            lineHeight: 1.3,
+          }}
+        >
           {inquiry.tenantName}
           {inquiry.tenantCompany ? ` · ${inquiry.tenantCompany}` : ''}
         </Typography>
-        <InquiryStatusBadge status={inquiry.status} />
+        {hasUnread && (
+          <Box
+            sx={{
+              minWidth: 20,
+              height: 20,
+              borderRadius: '50%',
+              bgcolor: '#2563eb',
+              color: 'white',
+              fontSize: '0.65rem',
+              fontWeight: 700,
+              display: 'flex',
+              alignItems: 'center',
+              justifyContent: 'center',
+              flexShrink: 0,
+              px: inquiry.unreadCount > 9 ? 0.75 : 0,
+            }}
+          >
+            {inquiry.unreadCount}
+          </Box>
+        )}
       </Box>
 
       <Typography
         variant="body2"
         sx={{
-          fontWeight: 500,
+          fontWeight: hasUnread ? 600 : 500,
           color: '#1e293b',
           fontSize: '0.85rem',
           display: '-webkit-box',