Seller Detail Screen

Full seller profile: avatar, métiers, follower count, products grid, prestations, reviews. Custom slide-from-right page transition reinforces the 'deeper into the catalog' navigation.

1. Reads handle from the GoRouter path param.
2. ref.watches sellerDetailProvider(handle) — renders SellerDetailShimmer while loading.
3. Follow / unfollow CTA dispatches into the follow_service (not in this feature) and invalidates the detail provider.
4. Tapping a product/prestation pushes the appropriate detail route.

• Deep-link from a notification or shared URL works because the screen reads pathParameters['handle'] and refetches on cold start.
• 404 errors render an empty state with a 'Back to search' CTA.

• lib/src/features/shared/search/screens/seller_detail_screen.dart
• lib/src/features/shared/search/widgets/seller_detail_shimmer.dart

Avatar tap doesn't open a full-screen photo viewer today — design decision, not bug.