Fix Flask-WTF CSRF import error for Flask-WTF 1.2.1 compatibility

- Initialize CSRFProtect in app/__init__.py
- Update import in app/upload/routes.py from flask_wtf.csrf to flask_wtf
- Maintain existing @csrf.exempt decorators

app/__init__.py

@@ -4,6 +4,7 @@ from flask import Flask
 from flask_sqlalchemy import SQLAlchemy
 from flask_login import LoginManager
 from flask_jwt_extended import JWTManager
+from flask_wtf import CSRFProtect
 from config import config
 import colorlog
 from werkzeug.middleware.proxy_fix import ProxyFix
@@ -13,6 +14,7 @@ from werkzeug.middleware.proxy_fix import ProxyFix
 db = SQLAlchemy()
 login_manager = LoginManager()
 jwt = JWTManager()
+csrf = CSRFProtect()
 
 def create_app(config_name=None):
     """Application factory pattern"""
@@ -28,6 +30,7 @@ def create_app(config_name=None):
     db.init_app(app)
     login_manager.init_app(app)
     jwt.init_app(app)
+    csrf.init_app(app)
     
     # Configure login manager
     login_manager.login_view = 'auth.login'

app/upload/routes.py

@@ -5,7 +5,7 @@ import shutil
 from flask import request, jsonify, render_template, redirect, url_for, flash, current_app
 from flask_login import login_required, current_user
 from flask_jwt_extended import jwt_required, get_jwt_identity
-from flask_wtf.csrf import csrf
+from flask_wtf import csrf
 from werkzeug.utils import secure_filename
 from app.upload import bp
 from app import db