feat: integrate SvelteKit for seamless navigation and improved data loading

backend/src/app.py

@@ -13,7 +13,10 @@ sys.path.append(str(project_root))
 
 from fastapi import FastAPI, WebSocket, WebSocketDisconnect, Depends
 from fastapi.middleware.cors import CORSMiddleware
+from fastapi.staticfiles import StaticFiles
+from fastapi.responses import FileResponse
 import asyncio
+import os
 
 from .dependencies import get_task_manager
 from .core.logger import logger
@@ -69,10 +72,26 @@ async def websocket_endpoint(websocket: WebSocket, task_id: str, task_manager=De
 
 # [/DEF]
 
-# [DEF:RootEndpoint:Endpoint]
-# @SEMANTICS: root, healthcheck
-# @PURPOSE: A simple root endpoint to confirm that the API is running.
-@app.get("/")
-async def read_root():
-    return {"message": "Superset Tools API is running"}
+# [DEF:StaticFiles:Mount]
+# @SEMANTICS: static, frontend, spa
+# @PURPOSE: Mounts the frontend build directory to serve static assets.
+frontend_path = project_root / "frontend" / "build"
+if frontend_path.exists():
+    app.mount("/_app", StaticFiles(directory=str(frontend_path / "_app")), name="static")
+    
+    # Serve other static files from the root of build directory
+    @app.get("/{file_path:path}")
+    async def serve_spa(file_path: str):
+        full_path = frontend_path / file_path
+        if full_path.is_file():
+            return FileResponse(str(full_path))
+        # Fallback to index.html for SPA routing
+        return FileResponse(str(frontend_path / "index.html"))
+else:
+    # [DEF:RootEndpoint:Endpoint]
+    # @SEMANTICS: root, healthcheck
+    # @PURPOSE: A simple root endpoint to confirm that the API is running.
+    @app.get("/")
+    async def read_root():
+        return {"message": "Superset Tools API is running (Frontend build not found)"}
 # [/DEF]