- shipping_handler: Remove auth restriction on GetShippingSettings (buyers need to see sellers' shipping options)
- order_handler: Add role query param parsing (buyer/seller) to filter orders by requester's company ID
Fixes 500 errors on:
- GET /api/v1/shipping/settings/{vendor_id}
- GET /api/v1/orders?role=buyer
- GET /api/v1/orders?role=seller
- ProductOffersModal: Add quantity input for each offer when purchasing
- ProductOffersModal: Display offer info in single line with flex-wrap
- GroupedProductCard: Add whitespace-nowrap to prevent 'oferta' badge wrapping
- ProductSearch: Swap Filters and Location components (Filters now first)
- Backend: Refactored admin routes to use role-based access control
- review_handler: New handler with role-based filtering
- shipping_handler: Added ListShipments with role-based filtering
- domain/models: Added SellerID to ReviewFilter and ShipmentFilter
- postgres.go: Updated ListReviews and ListShipments for SellerID filtering
- server.go: Removed /api/v1/admin routes, updated handlers
