feat(auth): implement user authentication with JWT and NextAuth

- Added user registration and login functionality with JWT authentication.
- Created auth controller, service, and module in the backend.
- Implemented user model and user products management.
- Integrated NextAuth for session management on the frontend.
- Added middleware for protecting routes and handling public access.
- Updated frontend API routes to include authorization headers.
- Enhanced recipe and user product models to support ownership and visibility.
- Created registration and login pages in the frontend.
- Added necessary types for NextAuth session management.

frontend/app/api/auth-register/route.ts

@@ -0,0 +1,17 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+const API_BASE = process.env.NEXT_PUBLIC_API_URL_INTERNAL || 'http://recipe-api:8080';
+
+export async function POST(request: NextRequest) {
+  const body = await request.json();
+  const res = await fetch(`${API_BASE}/api/auth/register`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify(body),
+  });
+  const text = await res.text();
+  return new NextResponse(text, {
+    status: res.status,
+    headers: { 'Content-Type': 'application/json' },
+  });
+}