docs: Remove obsolete volume_mode references from documentation

The volume_mode parameter is no longer used since workflows now upload files to MinIO storage instead of mounting volumes directly. This commit removes all references to volume_mode from:

- Backend API documentation (README.md)
- Tutorial getting started guide
- MCP integration guide
- CLI AI reference documentation
- SDK documentation and examples
- Test project documentation

All curl examples and code samples have been updated to reflect the current MinIO-based file upload approach.

test_projects/README.md

@@ -47,24 +47,21 @@ The vulnerable application can be tested with multiple security workflows:
 curl -X POST http://localhost:8000/workflows/security_assessment/submit \
   -H "Content-Type: application/json" \
   -d '{
-    "target_path": "/path/to/test_projects/vulnerable_app",
-    "volume_mode": "ro"
+    "target_path": "/path/to/test_projects/vulnerable_app"
   }'
 
 # Test Gitleaks secret detection workflow
 curl -X POST http://localhost:8000/workflows/gitleaks_detection/submit \
   -H "Content-Type: application/json" \
   -d '{
-    "target_path": "/path/to/test_projects/vulnerable_app",
-    "volume_mode": "ro"
+    "target_path": "/path/to/test_projects/vulnerable_app"
   }'
 
 # Test TruffleHog secret detection workflow
 curl -X POST http://localhost:8000/workflows/trufflehog_detection/submit \
   -H "Content-Type: application/json" \
   -d '{
-    "target_path": "/path/to/test_projects/vulnerable_app",
-    "volume_mode": "ro"
+    "target_path": "/path/to/test_projects/vulnerable_app"
   }'
 ```