feat: Add UX optimizations - skeletons and optimistic hooks

- Add Skeletons.tsx with TastingListSkeleton, ChartSkeleton, etc.
- Add useOptimistic.ts hooks for React 19 optimistic updates
- Update stats page to use skeleton loading instead of spinner
- Remove force-dynamic exports (12 files) for SSG compatibility
- Note: PPR (cacheComponents) tested but reverted - requires RSC-first refactor

src/app/admin/banners/page.tsx

@@ -1,4 +1,3 @@
-export const dynamic = 'force-dynamic';
 
 import { createClient } from '@/lib/supabase/server';
 import { redirect } from 'next/navigation';