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/BookingPreviewModal.vue

@@ -19,7 +19,21 @@
             <span>{{ booking.space?.name || 'Unknown Space' }}</span>
           </div>
 
-          <div v-if="isAdmin && booking.user" class="detail-row">
+          <div v-if="booking.is_anonymous && booking.guest_name" class="detail-row">
+            <UserIcon :size="16" class="detail-icon" />
+            <span>
+              {{ booking.guest_name }}
+              <span class="detail-guest-badge">Guest</span>
+              <span v-if="booking.guest_email" class="detail-muted">
+                &middot; {{ booking.guest_email }}
+              </span>
+              <span v-if="booking.guest_organization" class="detail-muted">
+                &middot; {{ booking.guest_organization }}
+              </span>
+            </span>
+          </div>
+
+          <div v-else-if="isAdmin && booking.user" class="detail-row">
             <UserIcon :size="16" class="detail-icon" />
             <span>
               {{ booking.user.full_name }}
@@ -127,7 +141,7 @@ const actionButtons = computed<ActionButton[]>(() => {
     buttons.push({ key: 'reject', label: 'Reject', icon: XCircle })
   }
 
-  if (status === 'pending') {
+  if (status === 'pending' || status === 'approved') {
     buttons.push({ key: 'edit', label: 'Edit', icon: Pencil })
   }
 
@@ -273,6 +287,18 @@ onUnmounted(() => {
   color: var(--color-text-muted);
 }
 
+.detail-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;
+}
+
 /* Description */
 .preview-description {
   background: var(--color-bg-secondary);