refactor: unit-centric lease view — Einheiten & Mietverträge

Replace building-level Miet- & Mieterinformationen section with
unit-level lease display. Each unit row now shows tenant name and
lease end date directly; expand reveals full contract details
(Mietbeginn, Mietende, Laufzeit, Breakout, source system, doc link).

Floor grouping groups consecutive same-floor units under one label.
Domain model extended with Lease and Tenant types; deprecated
property-level tenant fields preserved via @deprecated for compat.

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

src/features/matching/matchCardAdapter.ts

@@ -11,8 +11,9 @@ import type {
   MatchCardReason,
 } from '../../components/match-card/MatchCardViewModel'
 import { getCityIntelligence } from '../../lib/locationIntelligence'
-import { formatUnitTitle, formatMultiUnitFloors } from '../../domain/unit'
+import { formatUnitTitle, formatMultiUnitFloors, getUnitAvailability } from '../../domain/unit'
 import { calcFitOutInvestment } from '../../lib/fitOutUtils'
+import { AvailabilityStatus } from '../../domain/enums'
 
 const HARD_CRITERIA = new Set(['area', 'location', 'budget', 'timing'])
 
@@ -69,9 +70,19 @@ export function buildMatchCardViewModel(
     cardTitle = property?.title ?? signal?.companyName ?? signal?.locationHint ?? '–'
   }
 
-  const availabilityLabel =
-    property?.availabilityDate ??
-    (signal?.timeHorizonMonths ? `~${signal.timeHorizonMonths} Monate` : undefined)
+  // Prefer unit-level availability (from Lease), fall back to property-level date, then signal
+  const unitAvail = unit ? getUnitAvailability(unit) : null
+  const availabilityLabel = (() => {
+    if (unitAvail?.availableFrom) {
+      return `ab ${new Date(unitAvail.availableFrom).toLocaleDateString('de-CH', { month: 'short', year: '2-digit' })}`
+    }
+    if (unitAvail?.status === AvailabilityStatus.AVAILABLE_NOW) return 'Sofort verfügbar'
+    if (property?.availabilityDate) {
+      return `ab ${new Date(property.availabilityDate).toLocaleDateString('de-CH', { month: 'short', year: '2-digit' })}`
+    }
+    if (signal?.timeHorizonMonths) return `~${signal.timeHorizonMonths} Monate`
+    return undefined
+  })()
 
   const sourceLabel =
     property?.sourceLabel ??
@@ -134,6 +145,8 @@ export function buildMatchCardViewModel(
     signalConfirmedFacts: signal?.confirmedFacts,
     signalUnconfirmedFacts: signal?.unconfirmedFacts,
     signalAreaSqmEstimate: signal?.areaSqmEstimate,
+    areaSqm: unit?.areaSqm ?? property?.areaSqm ?? signal?.areaSqmEstimate,
+    rentPerSqm: property?.rentPricePerSqm,
     propertyId: property?.id ?? signal?.propertyId,
     unitId: match.unitId ?? unit?.id ?? signal?.unitId,
     preMarketUnit: unit,