feat: complete modular platform architecture (Phases 1-5)

Phase 1 - Vendor Router Integration:
- Wire up vendor module routers in app/api/v1/vendor/__init__.py
- Use lazy imports via __getattr__ to avoid circular dependencies

Phase 2 - Extract Remaining Modules:
- Create 6 new module directories: customers, cms, analytics, messaging,
  dev_tools, monitoring
- Each module has definition.py and route wrappers
- Update registry to import from extracted modules

Phase 3 - Database Table Migration:
- Add PlatformModule junction table for auditable module tracking
- Add migration zc2m3n4o5p6q7_add_platform_modules_table.py
- Add modules relationship to Platform model
- Update ModuleService with JSON-to-junction-table migration

Phase 4 - Module-Specific Configuration UI:
- Add /api/v1/admin/module-config/* endpoints
- Add module-config.html template and JS

Phase 5 - Integration Tests:
- Add tests/fixtures/module_fixtures.py
- Add tests/integration/api/v1/admin/test_modules.py
- Add tests/integration/api/v1/modules/test_module_access.py

Architecture fixes:
- Fix JS-003 errors: use ...data() directly in Alpine components
- Fix JS-005 warnings: add init() guards to prevent duplicate init
- Fix API-001 errors: add MenuActionResponse Pydantic model
- Add FE-008 noqa for dynamic number input in template

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

app/modules/dev_tools/__init__.py

@@ -0,0 +1,21 @@
+# app/modules/dev_tools/__init__.py
+"""
+Dev-Tools Module - Developer tools and utilities.
+
+This module provides:
+- Component library browser
+- Icon browser
+- Development utilities
+
+Routes:
+- Admin: (page routes only, minimal API)
+- Vendor: None
+
+Menu Items:
+- Admin: components, icons
+- Vendor: None
+"""
+
+from app.modules.dev_tools.definition import dev_tools_module
+
+__all__ = ["dev_tools_module"]

app/modules/dev_tools/definition.py

@@ -0,0 +1,35 @@
+# app/modules/dev_tools/definition.py
+"""
+Dev-Tools module definition.
+
+Defines the dev-tools module including its features, menu items,
+and route configurations.
+
+Note: This module primarily provides page routes, not API routes.
+"""
+
+from app.modules.base import ModuleDefinition
+from models.database.admin_menu_config import FrontendType
+
+
+# Dev-Tools module definition
+dev_tools_module = ModuleDefinition(
+    code="dev-tools",
+    name="Developer Tools",
+    description="Component library and icon browser for development.",
+    features=[
+        "component_library",  # UI component browser
+        "icon_browser",  # Icon library browser
+    ],
+    menu_items={
+        FrontendType.ADMIN: [
+            "components",  # Component library page
+            "icons",  # Icon browser page
+        ],
+        FrontendType.VENDOR: [],  # No vendor menu items
+    },
+    is_core=False,
+)
+
+
+__all__ = ["dev_tools_module"]

app/modules/dev_tools/routes/__init__.py

@@ -0,0 +1,15 @@
+# app/modules/dev_tools/routes/__init__.py
+"""
+Dev-Tools module route registration.
+
+This module provides functions to register dev-tools routes
+with module-based access control.
+
+Note: Dev-Tools module has primarily page routes, not API routes.
+The page routes are defined in admin/vendor page handlers.
+"""
+
+# Dev-tools has minimal API routes - primarily page routes
+# No auto-imports needed
+
+__all__ = []