Refactor: Implement API and cache improvements

src/lib/queryKeys.ts

@@ -88,6 +88,11 @@ export const queryKeys = {
   // Admin queries
   admin: {
     versionAudit: ['admin', 'version-audit'] as const,
+    settings: () => ['admin-settings'] as const,
+    blogPosts: () => ['admin-blog-posts'] as const,
+    contactSubmissions: (statusFilter?: string, categoryFilter?: string, searchQuery?: string, showArchived?: boolean) => 
+      ['admin-contact-submissions', statusFilter, categoryFilter, searchQuery, showArchived] as const,
+    auditLogs: (userId?: string) => ['admin', 'audit-logs', userId] as const,
   },
   
   // Moderation queries