Add paidAt field and display to order details and table

Introduces the optional 'paidAt' field to the Order interface and updates both the order details page and the order table to display the payment date. Also adds sorting by 'paidAt' in the order table and improves date formatting for both order and payment dates.

components/tables/order-table.tsx

@@ -53,6 +53,7 @@ interface Order {
   status: string;
   totalPrice: number;
   orderDate: Date;
+  paidAt?: Date;
   telegramUsername?: string;
   telegramBuyerId?: string;
   underpaid?: boolean;
@@ -61,7 +62,7 @@ interface Order {
   cryptoTotal?: number;
 }
 
-type SortableColumns = "orderId" | "totalPrice" | "status" | "orderDate";
+type SortableColumns = "orderId" | "totalPrice" | "status" | "orderDate" | "paidAt";
 
 interface StatusConfig {
   icon: React.ElementType;
@@ -433,7 +434,10 @@ export default function OrderTable() {
                     Status <ArrowUpDown className="ml-2 inline h-4 w-4" />
                   </TableHead>
                   <TableHead className="cursor-pointer" onClick={() => handleSort("orderDate")}>
-                    Date <ArrowUpDown className="ml-2 inline h-4 w-4" />
+                    Order Date <ArrowUpDown className="ml-2 inline h-4 w-4" />
+                  </TableHead>
+                  <TableHead className="cursor-pointer" onClick={() => handleSort("paidAt")}>
+                    Paid At <ArrowUpDown className="ml-2 inline h-4 w-4" />
                   </TableHead>
                   <TableHead>Buyer</TableHead>
                   <TableHead className="w-24 text-center">Actions</TableHead>
@@ -492,6 +496,16 @@ export default function OrderTable() {
                           hour12: false
                         })}
                       </TableCell>
+                      <TableCell>
+                        {order.paidAt ? new Date(order.paidAt).toLocaleDateString("en-GB", {
+                          day: '2-digit',
+                          month: 'short',
+                          year: 'numeric',
+                          hour: '2-digit',
+                          minute: '2-digit',
+                          hour12: false
+                        }) : "-"}
+                      </TableCell>
                       <TableCell>
                         {order.telegramUsername ? `@${order.telegramUsername}` : "-"}
                       </TableCell>