Add comprehensive social media management system and improve admin pages

## Social Media Management System
- Add SocialMediaLink database model with platform, URL, icon, and ordering
- Create complete CRUD API endpoints for admin social media management
- Implement admin social media management page with Material-UI DataGrid
- Add "Social Media" menu item to admin navigation
- Update footer to dynamically load and display enabled social media links
- Support multiple platforms: Facebook, Twitter, Instagram, YouTube, LinkedIn, GitHub, TikTok
- Include proper icon mapping and fallback handling

## Admin Pages Improvements
- Replace broken TinyMCE editor with working WYSIWYG rich text editor
- Create SimpleRichEditor component with toolbar for formatting
- Fix admin authentication to use cookies instead of localStorage tokens
- Update all admin API calls to use credentials: 'include'
- Increase content editor height to 800px for better editing experience
- Add Lexical editor component as alternative (not currently used)

## Footer Pages System
- Create 8 comprehensive footer pages: About, Blog, Support, API Docs, Terms, Privacy, Cookies, GDPR
- Implement dynamic footer link management with smart categorization
- Separate Quick Links and Legal sections with automatic filtering
- Remove duplicate hardcoded links and use database-driven system
- All footer pages are fully written with professional content

## Database & Dependencies
- Add uuid package for ID generation
- Update Prisma schema with new SocialMediaLink model and relations
- Seed default social media links for Facebook, Twitter, Instagram, YouTube
- Add Lexical rich text editor packages (@lexical/react, etc.)

## Technical Improvements
- Fix async params compatibility for Next.js 15
- Update MUI DataGrid deprecated props
- Improve admin layout navigation structure
- Add proper TypeScript interfaces for all new components
- Implement proper error handling and user feedback

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/admin/pages/page.tsx

@@ -69,15 +69,12 @@ export default function PagesManagement() {
 
   const fetchPages = async () => {
     try {
-      const token = localStorage.getItem('authToken');
       const params = new URLSearchParams();
       if (filterStatus !== 'all') params.append('status', filterStatus);
       if (searchQuery) params.append('search', searchQuery);
 
       const response = await fetch(`/api/admin/pages?${params.toString()}`, {
-        headers: {
-          'Authorization': `Bearer ${token}`
-        }
+        credentials: 'include'
       });
 
       if (!response.ok) {
@@ -113,12 +110,9 @@ export default function PagesManagement() {
     if (!pageToDelete) return;
 
     try {
-      const token = localStorage.getItem('authToken');
       const response = await fetch(`/api/admin/pages/${pageToDelete.id}`, {
         method: 'DELETE',
-        headers: {
-          'Authorization': `Bearer ${token}`
-        }
+        credentials: 'include'
       });
 
       if (!response.ok) {