fix(admin): forward cookies in SSR for admin/clubs endpoints

Root cause: Next.js server-side rendering was making API calls without
forwarding browser cookies, causing AUTHORIZATION_ERROR during page load.

Changes:
- Updated getAdminClubs() to accept optional cookieHeader parameter
- Updated getAdminClubDetail() to accept optional cookieHeader parameter
- Modified /admin/clubs page to extract cookies via next/headers and
  forward them to API calls during SSR
- Use credentials: 'omit' when manually setting Cookie header to avoid
  fetch() conflicts

Result: Admin endpoints now authenticate properly during SSR, allowing
page to render club list correctly instead of showing error state.

Resolves: SSR authorization error reported in BUILD:283 regression test

src/app/[locale]/admin/clubs/page.tsx

@@ -3,13 +3,18 @@ import { getTranslate } from '../../dictionaries';
 import { Building, AlertCircle, Lock } from 'lucide-react';
 import { getAdminClubs } from '@/src/lib/api/admin-clubs';
 import Link from 'next/link';
+import { cookies } from 'next/headers';
 
 export default async function AdminClubsPage({ params }: { params: Promise<{ locale: Locale }>}) {
   const { locale } = await params;
   const {t} = await getTranslate(locale);
 
+  // Get cookies for SSR auth
+  const cookieStore = await cookies();
+  const cookieHeader = cookieStore.toString();
+
   // Fetch clubs from API - this will handle auth states via HTTP status codes
-  const result = await getAdminClubs();
+  const result = await getAdminClubs(cookieHeader);
 
   // Handle authentication error (401)
   if (!result.success && result.error.status === 401) {

src/lib/api/admin-clubs.ts

@@ -62,16 +62,24 @@ async function handleApiResponse<T>(response: Response): Promise<AdminApiResult<
  * GET /admin/clubs
  * Lists all clubs the authenticated user can manage
  *
+ * @param cookieHeader - Optional cookie header to forward (for SSR)
  * @returns Array of clubs or error
  */
-export async function getAdminClubs(): Promise<AdminApiResult<AdminClubsResponse>> {
+export async function getAdminClubs(cookieHeader?: string): Promise<AdminApiResult<AdminClubsResponse>> {
   try {
+    const headers: Record<string, string> = {
+      'Content-Type': 'application/json',
+    };
+
+    // Forward cookies for server-side rendering
+    if (cookieHeader) {
+      headers['Cookie'] = cookieHeader;
+    }
+
     const response = await fetch(`${API_BASE_URL}/admin/clubs`, {
       method: 'GET',
-      headers: {
-        'Content-Type': 'application/json',
-      },
-      credentials: 'include', // Include cookies for auth
+      headers,
+      credentials: cookieHeader ? 'omit' : 'include', // Use 'omit' when manually setting Cookie header
     });
 
     return handleApiResponse<AdminClubsResponse>(response);
@@ -95,18 +103,27 @@ export async function getAdminClubs(): Promise<AdminApiResult<AdminClubsResponse
  * Gets detailed information about a specific club
  *
  * @param clubId - The club ID to fetch
+ * @param cookieHeader - Optional cookie header to forward (for SSR)
  * @returns Club details or error
  */
 export async function getAdminClubDetail(
-  clubId: number
+  clubId: number,
+  cookieHeader?: string
 ): Promise<AdminApiResult<AdminClubDetail>> {
   try {
+    const headers: Record<string, string> = {
+      'Content-Type': 'application/json',
+    };
+
+    // Forward cookies for server-side rendering
+    if (cookieHeader) {
+      headers['Cookie'] = cookieHeader;
+    }
+
     const response = await fetch(`${API_BASE_URL}/admin/clubs/${clubId}`, {
       method: 'GET',
-      headers: {
-        'Content-Type': 'application/json',
-      },
-      credentials: 'include', // Include cookies for auth
+      headers,
+      credentials: cookieHeader ? 'omit' : 'include', // Use 'omit' when manually setting Cookie header
     });
 
     return handleApiResponse<AdminClubDetail>(response);