feat: unit-level matching architecture — match against Einheiten, not Objekte

- domain/property: add getEffectiveUnits() — returns explicit units or synthesises
  one from property-level data so all properties work uniformly at unit level
- domain/match: add unitId? field — every Match references a specific unit
- domain/unifiedResult: add unit? to VerifiedPortfolioResult + ExternalMarketResult
- MockupNeedProvider: generateSyntheticMatches iterates getEffectiveUnits(prop);
  computeScore uses unit-level areaSqm + rentPricePerSqm; resultId for PRE-MARKET
  signals matches useSchattenmarktSignals signal ID format
- useUnifiedResults: resolve unit from match.unitId for VERIFIED_PORTFOLIO/EXTERNAL_MARKET
- matchCardAdapter: unit now extracted for all result types; unitId from match.unitId
- IntelligenceMatchCard: regular cards show unit chip (floor + label + m²) when a
  named unit is known — only adds context, never shows for synthetic/whole-property units

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

src/hooks/useUnifiedResults.ts

@@ -59,6 +59,11 @@ export function useUnifiedResults(needId?: string) {
             resultType: 'FUTURE_AVAILABILITY', signal, match, property, unit: backingUnit }]
         }
 
+        // Resolve specific unit if the match carries a unitId
+        const matchUnit = match.unitId
+          ? (property.units?.find(u => u.id === match.unitId) ?? undefined)
+          : undefined
+
         if (rt === 'EXTERNAL_MARKET' || rt === 'MAISON_WORK') {
           const result: ExternalMarketResult = {
             matchId: match.id,
@@ -67,6 +72,7 @@ export function useUnifiedResults(needId?: string) {
             resultType: rt as 'EXTERNAL_MARKET' | 'MAISON_WORK',
             property,
             match,
+            unit: matchUnit,
           }
           return [result]
         }
@@ -78,6 +84,7 @@ export function useUnifiedResults(needId?: string) {
           resultType: 'VERIFIED_PORTFOLIO',
           property,
           match,
+          unit: matchUnit,
         }
         return [result]
       })