fix UI

app.py

@@ -1,14 +1,14 @@
 import logging
 import gradio as gr
 from fastapi import FastAPI, Request
-import uvicorn
 from rag_core import business
+import uvicorn
 
 logging.basicConfig(level=logging.INFO, format="%(asctime)s [%(levelname)s] %(message)s")
 
 app = FastAPI()
 
-# === API ===
+# --- API Routes ---
 @app.post("/ask")
 async def ask_api(req: Request):
     data = await req.json()
@@ -18,7 +18,7 @@ async def ask_api(req: Request):
 async def rescan_api():
     return business.rescan_index()
 
-# === Gradio UI ===
+# --- Gradio UI logic ---
 def answer_fn(query):
     result = business.answer_query(query)
     return result.get("answer", result.get("error", "Lỗi không xác định."))
@@ -34,9 +34,10 @@ with gr.Blocks() as iface:
     query_box.submit(fn=answer_fn, inputs=query_box, outputs=output_box)
     build_btn.click(fn=build_index_ui, outputs=[build_btn, query_box, output_box])
 
-# Mount Gradio lên FastAPI
+# Mount Gradio vào ROOT path "/"
 app = gr.mount_gradio_app(app, iface, path="/")
 
+# Chạy server khi standalone
 if __name__ == "__main__":
     logging.info("🚀 Khởi chạy FastAPI + Gradio tại cổng 7860")
     uvicorn.run(app, host="0.0.0.0", port=7860)