add CORS headers

app.py

@@ -150,7 +150,7 @@ def plext_to_dict(plext: Plext) -> dict:
         ],
     }
 
-@app.route("/plexts/from-db", methods=["GET"])
+@app.route("/plexts/from-db", methods=["GET", "OPTIONS"])
 @basic_auth_required
 def get_plexts_from_db():
     """
@@ -164,6 +164,17 @@ def get_plexts_from_db():
     Returns:
         JSON response with list of plexts (without _id field)
     """
+    # CORS headers
+    cors_headers = {
+        "Access-Control-Allow-Origin": "*",
+        "Access-Control-Allow-Methods": "GET, OPTIONS",
+        "Access-Control-Allow-Headers": "Content-Type, Authorization",
+    }
+
+    # Handle OPTIONS preflight request
+    if request.method == "OPTIONS":
+        return "", 200, cors_headers
+
     try:
         # Parse query parameters
         player_name = request.args.get("player_name")
@@ -175,13 +186,13 @@ def get_plexts_from_db():
             try:
                 timestamp_from = int(timestamp_from)
             except ValueError:
-                return jsonify({"error": "timestamp_from must be an integer"}), 400
+                return jsonify({"error": "timestamp_from must be an integer"}), 400, cors_headers
 
         if timestamp_to is not None:
             try:
                 timestamp_to = int(timestamp_to)
             except ValueError:
-                return jsonify({"error": "timestamp_to must be an integer"}), 400
+                return jsonify({"error": "timestamp_to must be an integer"}), 400, cors_headers
 
         # Build MongoDB filter query
         filter_query = {}
@@ -222,17 +233,17 @@ def get_plexts_from_db():
             return jsonify({
                 "count": len(plexts),
                 "plexts": plexts
-            })
+            }), 200, cors_headers
 
         except PyMongoError as e:
             logger.error(f"MongoDB error: {e}")
-            return jsonify({"error": "Database error"}), 500
+            return jsonify({"error": "Database error"}), 500, cors_headers
         finally:
             client.close()
 
     except Exception as e:
         logger.exception("Unexpected error in get_plexts_from_db")
-        return jsonify({"error": "An error occurred"}), 500
+        return jsonify({"error": "An error occurred"}), 500, cors_headers
 
 @app.route("/plexts/from-api", methods=["GET"])
 @basic_auth_required