feat(blog): implement loading and error handling components for blog pages
feat(clinic): add loading and error handling components for clinic pages
feat(doctor): create loading and error handling components for doctor pages
feat(clinics): add loading component for clinics page
feat(specialties): improve metadata for specialties page with Open Graph and Twitter images
feat(layout): add structured data for Organization and WebSite in layout
fix(middleware): restrict middleware execution to specific routes to improve performance
chore(audit): add comprehensive SEO and performance audit documentation
