feat: add hotel and vehicle option site modules

Add full support for hotel group and vehicle option site management features:
- Define SQLAlchemy models and alembic migration for the new database tables
- Add default sample content entries in content.py
- Extend admin and public API routes to support the new modules
- Update seed script to populate default hotel and vehicle data
- Update all relevant documentation and test cases

app/routers/admin.py

@@ -20,6 +20,7 @@ from ..models import (
     CtaBanner,
     Destination,
     HeroSlide,
+    HotelGroup,
     Lead,
     MapImage,
     MediaAsset,
@@ -29,6 +30,7 @@ from ..models import (
     RouteSectionProduct,
     SiteVersion,
     ThemeCard,
+    VehicleOption,
     utc_now,
 )
 from ..schemas import AdminProductQuery, LeadQuery, LeadStatus, LeadStatusIn, LoginIn, ProductCreateIn, ProductStatus, ProductUpdateIn, SiteConfigPatchIn, SiteConfigReorderIn
@@ -103,6 +105,24 @@ SITE_CONFIG_MODULES = {
         "empty_to_none": {"subtitle"},
         "create_defaults": {},
     },
+    "hotelGroups": {
+        "model": HotelGroup,
+        "entity": "hotel_group",
+        "primary": "title",
+        "fields": {"title", "description", "image", "isActive", "sortOrder"},
+        "none_to_empty": set(),
+        "empty_to_none": {"description", "image"},
+        "create_defaults": {"description": None, "image": None},
+    },
+    "vehicleOptions": {
+        "model": VehicleOption,
+        "entity": "vehicle_option",
+        "primary": "title",
+        "fields": {"title", "description", "image", "isActive", "sortOrder"},
+        "none_to_empty": set(),
+        "empty_to_none": {"description", "image"},
+        "create_defaults": {"description": None, "image": None},
+    },
     "ctaBanners": {
         "model": CtaBanner,
         "entity": "cta_banner",
@@ -629,6 +649,14 @@ def admin_site_config(_user: AdminUser = Depends(require_admin), db: Session = D
             for item in db.scalars(select(Campaign).order_by(Campaign.updatedAt.desc())).all()
         ],
         "routeSections": [route_section_dict(item) for item in db.scalars(route_section_query()).all()],
+        "hotelGroups": [
+            model_dict(item)
+            for item in db.scalars(select(HotelGroup).order_by(HotelGroup.sortOrder.asc())).all()
+        ],
+        "vehicleOptions": [
+            model_dict(item)
+            for item in db.scalars(select(VehicleOption).order_by(VehicleOption.sortOrder.asc())).all()
+        ],
     }