feat: unit-first architecture — floor + street as primary card title

Every VERIFIED_PORTFOLIO property now has explicit units in mock data
(added to prop-002, prop-008, prop-009, prop-010, prop-011, prop-014).

PropertyUnit extracted to domain/unit.ts with formatFloorLabel,
formatUnitTitle, formatMultiUnitFloors helpers; re-exported from
property.ts so all existing imports are unaffected.

Cards now show floor + street as the primary title:
- Specific unit match: "1.OG Nord · Zollstrasse 12"
- Multi-unit (whole building): "1.OG–3.OG · Zollstrasse 12"
- EG retail: "EG Verkauf · Löwenplatz 3"
Building name (e.g. "Bürofläche Zollstrasse 12") appears as subtitle.
Both IntelligenceMatchCard (grid) and MatchCardCompact (list) updated.

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

src/domain/unit.ts

@@ -0,0 +1,74 @@
+// ── Rentable Unit — primary entity for demand-side matching ──────────────────
+//
+// A Property is the building/address container.
+// A PropertyUnit is what is actually rented: a specific floor, wing, or section.
+// Floor level is business-critical: retail needs EG for walk-in traffic,
+// offices can occupy upper floors, logistics needs ground-level loading access.
+
+export interface PropertyUnit {
+  id: string
+  propertyId?: string       // FK to parent Property
+  floorLevel: number        // 0=EG, 1=1.OG, -1=UG1
+  unitLabel?: string        // e.g. "Nord", "West", "Einheit A"
+  areaSqm: number
+  available: boolean
+  rentPricePerSqm?: number  // annual CHF/m²; falls back to property.rentPricePerSqm
+  currentTenant?: string
+  leaseTerm?: string
+  leaseEndDate?: string
+  // Flexible letting (Teilfläche)
+  isFlexible?: boolean
+  minLettableSqm?: number
+  offeredSqm?: number       // currently offered area (≤ areaSqm)
+  // Unit-level pre-market release
+  schattenmarktRelease?: {
+    enabled: boolean
+    availableFrom?: string  // ISO date
+  }
+}
+
+// A bundle groups multiple free units into a combined offer
+export interface UnitBundle {
+  unitIds: string[]
+  combinedSqm: number
+  label: string             // e.g. "1.OG + 2.OG"
+}
+
+// Result of unit-level need matching (used in supply-side detail views)
+export interface UnitNeedMatch {
+  needId: string
+  tenantName: string
+  tenantCompany?: string
+  requiredSqmMin: number
+  requiredSqmMax: number
+  matchScore: number
+  matchType: 'exact' | 'partial' | 'bundle'
+  suggestedSqm?: number
+}
+
+// ── Display helpers ───────────────────────────────────────────────────────────
+
+export function formatFloorLabel(level: number): string {
+  if (level === 0) return 'EG'
+  if (level < 0) return `UG${Math.abs(level)}`
+  return `${level}.OG`
+}
+
+/** Returns the primary display title for a specific unit: "1.OG Nord · Zollstrasse 12" */
+export function formatUnitTitle(
+  unit: PropertyUnit,
+  address: { street: string; houseNumber: string },
+): string {
+  const floor = formatFloorLabel(unit.floorLevel)
+  const label = unit.unitLabel ? ` ${unit.unitLabel}` : ''
+  return `${floor}${label} · ${address.street} ${address.houseNumber}`
+}
+
+/** Returns a compact floor-range string for multi-unit properties: "1.OG–3.OG" or "EG · 1.OG" */
+export function formatMultiUnitFloors(units: PropertyUnit[]): string {
+  const floors = [...new Set(units.map(u => u.floorLevel))].sort((a, b) => a - b)
+  if (floors.length === 0) return ''
+  if (floors.length === 1) return formatFloorLabel(floors[0])
+  if (floors.length === 2) return `${formatFloorLabel(floors[0])} · ${formatFloorLabel(floors[1])}`
+  return `${formatFloorLabel(floors[0])}–${formatFloorLabel(floors[floors.length - 1])}`
+}