Greatly reduce repeated code

functions/api/inactivity/_middleware.ts

@@ -1,15 +1,8 @@
-function makeResponse(body: string, status: number): Response {
-  return new Response(body, {
-    headers: {
-      "content-type": "application/json",
-    },
-    status,
-  });
-}
+import { jsonError } from "../../common.js";
 
 export async function onRequest(context: RequestContext) {
   if (!context.data.current_user)
-    return makeResponse('{"error":"You are not logged in"}', 401);
+    return jsonError("You are not logged in", 401);
 
   const { permissions } = context.data.current_user;
   const departments = {