Include UniAuth callback

web_view.py

@@ -352,5 +352,11 @@ def holiday_list() -> str:
     )
 
 
+@app.route("/callback")
+def auth_callback() -> tuple[str, int] | werkzeug.Response:
+    """Process the authentication callback."""
+    return UniAuth.auth.auth_callback()
+
+
 if __name__ == "__main__":
     app.run(host="0.0.0.0")