refactor: clean up legacy models and migrate remaining schemas

Delete empty stub files from models/database/:
- audit.py, backup.py, configuration.py, monitoring.py
- notification.py, payment.py, search.py, task.py

Delete re-export files:
- models/database/subscription.py → app.modules.billing.models
- models/database/architecture_scan.py → app.modules.dev_tools.models
- models/database/test_run.py → app.modules.dev_tools.models
- models/schema/subscription.py → app.modules.billing.schemas
- models/schema/marketplace.py (empty)
- models/schema/monitoring.py (empty)

Migrate schemas to canonical module locations:
- billing.py → app/modules/billing/schemas/
- vendor_product.py → app/modules/catalog/schemas/
- homepage_sections.py → app/modules/cms/schemas/

Keep as CORE (framework-level, used everywhere):
- models/schema/: admin, auth, base, company, email, image, media, team, vendor*
- models/database/: admin*, base, company, email, feature, media, platform*, user, vendor*

Update 30+ files to use canonical import locations.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/modules/cms/schemas/__init__.py

@@ -8,7 +8,7 @@ from app.modules.cms.schemas.content_page import (
     ContentPageCreate,
     ContentPageUpdate,
     ContentPageResponse,
-    HomepageSectionsResponse,
+    HomepageSectionsResponse as ContentPageHomepageSectionsResponse,
     SectionUpdateResponse,
     # Vendor schemas
     VendorContentPageCreate,
@@ -18,19 +18,46 @@ from app.modules.cms.schemas.content_page import (
     PublicContentPageResponse,
     ContentPageListItem,
 )
+from app.modules.cms.schemas.homepage_sections import (
+    # Translatable text
+    TranslatableText,
+    # Section components
+    HeroButton,
+    HeroSection,
+    FeatureCard,
+    FeaturesSection,
+    PricingSection,
+    CTASection,
+    # Main structure
+    HomepageSections,
+    # API schemas
+    SectionUpdateRequest,
+    HomepageSectionsResponse,
+)
 
 __all__ = [
-    # Admin
+    # Content Page - Admin
     "ContentPageCreate",
     "ContentPageUpdate",
     "ContentPageResponse",
-    "HomepageSectionsResponse",
+    "ContentPageHomepageSectionsResponse",
     "SectionUpdateResponse",
-    # Vendor
+    # Content Page - Vendor
     "VendorContentPageCreate",
     "VendorContentPageUpdate",
     "CMSUsageResponse",
-    # Public
+    # Content Page - Public
     "PublicContentPageResponse",
     "ContentPageListItem",
+    # Homepage Sections
+    "TranslatableText",
+    "HeroButton",
+    "HeroSection",
+    "FeatureCard",
+    "FeaturesSection",
+    "PricingSection",
+    "CTASection",
+    "HomepageSections",
+    "SectionUpdateRequest",
+    "HomepageSectionsResponse",
 ]