Adds Kubernetes sandbox provisioner support (#35)

* Adds Kubernetes sandbox provisioner support

* Improves Docker dev setup by standardizing host paths

Replaces hardcoded host paths with a configurable root directory,
making the development environment more portable and easier to use
across different machines. Automatically sets the root path if not
already defined, reducing manual setup steps.

backend/src/gateway/routers/artifacts.py

@@ -1,3 +1,4 @@
+import logging
 import mimetypes
 import zipfile
 from pathlib import Path
@@ -8,6 +9,8 @@ from fastapi.responses import FileResponse, HTMLResponse, PlainTextResponse, Res
 
 from src.gateway.path_utils import resolve_thread_virtual_path
 
+logger = logging.getLogger(__name__)
+
 router = APIRouter(prefix="/api", tags=["artifacts"])
 
 
@@ -126,6 +129,8 @@ async def get_artifact(thread_id: str, path: str, request: Request) -> FileRespo
 
     actual_path = resolve_thread_virtual_path(thread_id, path)
 
+    logger.info(f"Resolving artifact path: thread_id={thread_id}, requested_path={path}, actual_path={actual_path}")
+
     if not actual_path.exists():
         raise HTTPException(status_code=404, detail=f"Artifact not found: {path}")