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/admin/products/actions.ts

@@ -2,6 +2,7 @@
 
 import { revalidatePath } from 'next/cache';
 import { API_BASE } from '../../../lib/api';
+import { getAuthHeaders } from '../../../lib/auth-headers';
 
 export async function updateProduct(formData: FormData) {
   const id = Number(formData.get('id'));
@@ -20,7 +21,7 @@ export async function updateProduct(formData: FormData) {
 
   const res = await fetch(`${API_BASE}/api/products/${id}`, {
     method: 'PATCH',
-    headers: { 'Content-Type': 'application/json' },
+    headers: { 'Content-Type': 'application/json', ...(await getAuthHeaders()) },
     body: JSON.stringify({
       name: name || undefined,
       canonicalName: canonicalName || undefined,
@@ -42,7 +43,7 @@ export async function updateProduct(formData: FormData) {
 export async function setProductTags(productId: number, tags: string[]) {
   const res = await fetch(`${API_BASE}/api/products/${productId}/tags`, {
     method: 'PUT',
-    headers: { 'Content-Type': 'application/json' },
+    headers: { 'Content-Type': 'application/json', ...(await getAuthHeaders()) },
     body: JSON.stringify({ tags }),
     cache: 'no-store',
   });
@@ -58,6 +59,7 @@ export async function setProductTags(productId: number, tags: string[]) {
 export async function deleteProduct(id: number) {
   const res = await fetch(`${API_BASE}/api/products/${id}`, {
     method: 'DELETE',
+    headers: { ...(await getAuthHeaders()) },
     cache: 'no-store',
   });