feat: add multi-tenant system with properties, organizations, and public booking

Implement complete multi-property architecture:
- Properties (groups of spaces) with public/private visibility
- Property managers (many-to-many) with role-based permissions
- Organizations with member management
- Anonymous/guest booking support via public API (/api/public/*)
- Property-scoped spaces, bookings, and settings
- Frontend: property selector, organization management, public booking views
- Migration script and updated seed data

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

frontend/src/components/BookingRow.vue

@@ -3,9 +3,17 @@
     <div class="row-time">
       {{ formatTimeRange(booking.start_datetime, booking.end_datetime) }}
     </div>
-    <div class="row-space">{{ booking.space?.name || 'Space' }}</div>
-    <div v-if="showUser && booking.user" class="row-user">
-      {{ booking.user.full_name }}
+    <div class="row-space">
+      {{ booking.space?.name || 'Space' }}
+      <span v-if="booking.space?.property_name" class="row-property">{{ booking.space.property_name }}</span>
+    </div>
+    <div v-if="showUser" class="row-user">
+      <template v-if="booking.is_anonymous && booking.guest_name">
+        {{ booking.guest_name }} <span class="guest-badge">Guest</span>
+      </template>
+      <template v-else-if="booking.user">
+        {{ booking.user.full_name }}
+      </template>
     </div>
     <div class="row-title" :title="booking.title">{{ booking.title }}</div>
     <span :class="['row-badge', `row-badge-${booking.status}`]">
@@ -136,6 +144,18 @@ const formatTimeRange = (start: string, end: string): string => {
   color: var(--color-accent);
   white-space: nowrap;
   min-width: 80px;
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+
+.row-property {
+  font-size: 10px;
+  font-weight: 600;
+  color: var(--color-text-muted);
+  background: var(--color-bg-tertiary);
+  padding: 1px 6px;
+  border-radius: 6px;
 }
 
 .row-user {
@@ -188,6 +208,18 @@ const formatTimeRange = (start: string, end: string): string => {
   color: var(--color-text-muted);
 }
 
+.guest-badge {
+  display: inline-block;
+  padding: 1px 6px;
+  font-size: 10px;
+  font-weight: 600;
+  border-radius: 6px;
+  background: color-mix(in srgb, var(--color-warning) 15%, transparent);
+  color: var(--color-warning);
+  vertical-align: middle;
+  margin-left: 4px;
+}
+
 @media (max-width: 640px) {
   .booking-row {
     flex-wrap: wrap;