Update app.py

app.py

@@ -2,6 +2,7 @@ from flask import Flask, request, jsonify, render_template
 import fitz  # PyMuPDF for PDF text extraction
 import faiss  # FAISS for vector search
 import numpy as np
+import os
 from sentence_transformers import SentenceTransformer
 from huggingface_hub import InferenceClient
 from typing import List, Tuple