refactor: complete module-driven architecture migration

This commit completes the migration to a fully module-driven architecture:

## Models Migration
- Moved all domain models from models/database/ to their respective modules:
  - tenancy: User, Admin, Vendor, Company, Platform, VendorDomain, etc.
  - cms: MediaFile, VendorTheme
  - messaging: Email, VendorEmailSettings, VendorEmailTemplate
  - core: AdminMenuConfig
- models/database/ now only contains Base and TimestampMixin (infrastructure)

## Schemas Migration
- Moved all domain schemas from models/schema/ to their respective modules:
  - tenancy: company, vendor, admin, team, vendor_domain
  - cms: media, image, vendor_theme
  - messaging: email
- models/schema/ now only contains base.py and auth.py (infrastructure)

## Routes Migration
- Moved admin routes from app/api/v1/admin/ to modules:
  - menu_config.py -> core module
  - modules.py -> tenancy module
  - module_config.py -> tenancy module
- app/api/v1/admin/ now only aggregates auto-discovered module routes

## Menu System
- Implemented module-driven menu system with MenuDiscoveryService
- Extended FrontendType enum: PLATFORM, ADMIN, VENDOR, STOREFRONT
- Added MenuItemDefinition and MenuSectionDefinition dataclasses
- Each module now defines its own menu items in definition.py
- MenuService integrates with MenuDiscoveryService for template rendering

## Documentation
- Updated docs/architecture/models-structure.md
- Updated docs/architecture/menu-management.md
- Updated architecture validation rules for new exceptions

## Architecture Validation
- Updated MOD-019 rule to allow base.py in models/schema/
- Created core module exceptions.py and schemas/ directory
- All validation errors resolved (only warnings remain)

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

app/modules/dev_tools/locales/de.json

@@ -1 +1,12 @@
-{}
+{
+  "messages": {
+    "test_run_started": "Test run started...",
+    "failed_to_copy_code": "Failed to copy code",
+    "failed_to_copy_name": "Failed to copy name",
+    "added_to_cart": "Added to cart!",
+    "filters_applied": "Filters applied!",
+    "review_submitted_successfully": "Review submitted successfully!",
+    "thanks_for_your_feedback": "Thanks for your feedback!",
+    "code_copied_to_clipboard": "Code copied to clipboard!"
+  }
+}

app/modules/dev_tools/locales/en.json

@@ -1 +1,12 @@
-{}
+{
+  "messages": {
+    "test_run_started": "Test run started...",
+    "failed_to_copy_code": "Failed to copy code",
+    "failed_to_copy_name": "Failed to copy name",
+    "added_to_cart": "Added to cart!",
+    "filters_applied": "Filters applied!",
+    "review_submitted_successfully": "Review submitted successfully!",
+    "thanks_for_your_feedback": "Thanks for your feedback!",
+    "code_copied_to_clipboard": "Code copied to clipboard!"
+  }
+}

app/modules/dev_tools/locales/fr.json

@@ -1 +1,12 @@
-{}
+{
+  "messages": {
+    "test_run_started": "Test run started...",
+    "failed_to_copy_code": "Failed to copy code",
+    "failed_to_copy_name": "Failed to copy name",
+    "added_to_cart": "Added to cart!",
+    "filters_applied": "Filters applied!",
+    "review_submitted_successfully": "Review submitted successfully!",
+    "thanks_for_your_feedback": "Thanks for your feedback!",
+    "code_copied_to_clipboard": "Code copied to clipboard!"
+  }
+}

app/modules/dev_tools/locales/lb.json

@@ -1 +1,12 @@
-{}
+{
+  "messages": {
+    "test_run_started": "Test run started...",
+    "failed_to_copy_code": "Failed to copy code",
+    "failed_to_copy_name": "Failed to copy name",
+    "added_to_cart": "Added to cart!",
+    "filters_applied": "Filters applied!",
+    "review_submitted_successfully": "Review submitted successfully!",
+    "thanks_for_your_feedback": "Thanks for your feedback!",
+    "code_copied_to_clipboard": "Code copied to clipboard!"
+  }
+}