Wire shop UI to RPCs and auto-equip after purchase.

Refactor client storage to call Supabase RPCs and equip items immediately after a successful buy.

Author: RecentRunner

components/shop/shop-content.tsx

@@ -147,7 +147,8 @@ export function ShopContent() {
 
     try {
       const item = await purchaseShopItem(itemId);
-      toast(`Purchased ${item.name}.`, "success");
+      await equipShopItem(itemId);
+      toast(`Purchased and equipped ${item.name}.`, "success");
       await refreshShop();
     } catch (purchaseError) {
       toast(