feat: complete dev_tools module self-containment

Migrate dev_tools module to self-contained structure:

- routes/api/ - API endpoints
- models/architecture_scan.py - Architecture scan models
- models/test_run.py - Test run models
- schemas/ - Pydantic schemas
- services/ - Business logic services
- tasks/ - Celery background tasks
- exceptions.py - Module exceptions

Updated definition.py with self-contained paths.

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

app/modules/dev_tools/routes/api/admin.py

@@ -0,0 +1,35 @@
+# app/modules/dev_tools/routes/api/admin.py
+"""
+Dev-Tools Admin API Routes.
+
+Provides admin-only API endpoints for:
+- Code quality scanning (architecture, security, performance)
+- Violation management
+- Test execution
+
+Note: This currently re-exports routes from legacy locations.
+In future cleanup phases, the route implementations may be moved here.
+"""
+
+from fastapi import APIRouter
+
+# Import the existing routers from legacy locations
+from app.api.v1.admin.code_quality import router as code_quality_router
+from app.api.v1.admin.tests import router as tests_router
+
+# Create a combined admin router for the dev-tools module
+admin_router = APIRouter(prefix="/dev-tools", tags=["dev-tools"])
+
+# Include sub-routers
+admin_router.include_router(
+    code_quality_router,
+    prefix="/code-quality",
+    tags=["code-quality"],
+)
+admin_router.include_router(
+    tests_router,
+    prefix="/tests",
+    tags=["tests"],
+)
+
+__all__ = ["admin_router"]