Add CSV export for orders and update UI symbols

Introduces an exportOrdersToCSV function in lib/api-client.ts to allow exporting orders by status as a CSV file. Updates various UI components to use the '•' (bullet) symbol instead of '·' (middle dot) and replaces some emoji/unicode characters for improved consistency and compatibility. Also normalizes the 'use client' directive to include a BOM in many files.

components/dashboard/promotions/PromotionsList.tsx

@@ -1,4 +1,4 @@
-'use client';
+'use client';
 
 import { useState, useEffect } from 'react';
 import { Plus, Tag, RefreshCw, Trash, Edit, Check, X, Eye } from 'lucide-react';
@@ -184,7 +184,7 @@ export default function PromotionsList() {
                         : 'None'}
                     </TableCell>
                     <TableCell>
-                      {promotion.usageCount} / {promotion.maxUsage || '∞'}
+                      {promotion.usageCount} / {promotion.maxUsage || 'Ôê×'}
                     </TableCell>
                     <TableCell>{formatDate(promotion.endDate)}</TableCell>
                     <TableCell>
@@ -306,4 +306,4 @@ export default function PromotionsList() {
       />
     </>
   );
-} 
+}