feat: upgrade next-auth to v5.0.0-beta.29 and refactor authentication middleware

- Updated next-auth dependency in package.json to version 5.0.0-beta.29.
- Refactored create-admin script to use a valid email format.
- Implemented authentication middleware for various API routes to enforce access control.
- Refactored API route handlers to improve readability and maintainability.
- Enhanced error handling in authentication error page.
- Added detailed tests for authentication flow, including protected routes and NextAuth endpoints.

src/app/api/tasks/route.js

@@ -1,8 +1,9 @@
 import db from "@/lib/db";
 import { NextResponse } from "next/server";
+import { withUserAuth } from "@/lib/middleware/auth";
 
 // POST: create new template
-export async function POST(req) {
+async function createTaskHandler(req) {
 	const { name, max_wait_days, description } = await req.json();
 
 	if (!name) {
@@ -18,3 +19,6 @@ export async function POST(req) {
 
 	return NextResponse.json({ success: true });
 }
+
+// Protected routes - require authentication
+export const POST = withUserAuth(createTaskHandler);