Almost Heaven style/admin repair pass

Changed:
- Fixed broken header/footer shell so pages render as one valid document
- Added live footer stats (listeners + visitors online)
- Applied shared Heaven visual cleanup across public pages without replacing station branding
- Stopped admin footer from sitting over content
- Added File Finder back into admin dashboard + top quick links

Files changed:
- header.php
- footer.php
- css/merged-smurf.css
- admin/assets/admin-v2.css
- admin/includes/admin_header.php
- admin/dashboard.php
