fix: Implement responsive Drawer for payment gateway settings on mobile

Problem: Payment gateway settings modal was using Dialog on all screen sizes
Solution: Split into responsive Dialog (desktop) and Drawer (mobile)

Changes:
1. Added Drawer and useMediaQuery imports
2. Added isDesktop hook: useMediaQuery("(min-width: 768px)")
3. Split modal into two conditional renders:
   - Desktop (≥768px): Dialog with horizontal footer layout
   - Mobile (<768px): Drawer with vertical footer layout

Desktop Layout (Dialog):
- Center modal overlay
- Horizontal footer: Cancel | View in WC | Save
- max-h-[80vh] for scrolling

Mobile Layout (Drawer):
- Bottom sheet (slides up from bottom)
- Vertical footer (full width buttons):
  1. Save Settings (primary)
  2. View in WooCommerce (ghost)
  3. Cancel (outline)
- max-h-[90vh] for more screen space
- Swipe down to dismiss

Benefits:
✅ Native mobile experience with bottom sheet
✅ Easier to reach buttons on mobile (bottom of screen)
✅ Better one-handed use
✅ Swipe gesture to dismiss
✅ Desktop keeps familiar modal experience

User Changes Applied:
- AlertDialog z-index: z-50 → z-[999] (higher than other modals)
- Dialog max-height: max-h-[100vh] → max-h-[80vh] (better desktop UX)

Files Modified:
- Payments.tsx: Responsive Dialog/Drawer implementation
- alert-dialog.tsx: Increased z-index for proper layering

admin-spa/src/routes/Settings/Payments.tsx

@@ -8,9 +8,11 @@ import { GenericGatewayForm } from '@/components/settings/GenericGatewayForm';
 import { Button } from '@/components/ui/button';
 import { Badge } from '@/components/ui/badge';
 import { Dialog, DialogContent, DialogHeader, DialogTitle } from '@/components/ui/dialog';
+import { Drawer, DrawerContent, DrawerHeader, DrawerTitle } from '@/components/ui/drawer';
 import { Alert, AlertDescription } from '@/components/ui/alert';
 import { CreditCard, Banknote, Settings, RefreshCw, ExternalLink, Loader2, AlertTriangle } from 'lucide-react';
 import { toast } from 'sonner';
+import { useMediaQuery } from '@/hooks/use-media-query';
 
 interface GatewayField {
   id: string;
@@ -55,6 +57,7 @@ export default function PaymentsPage() {
   const [selectedGateway, setSelectedGateway] = useState<PaymentGateway | null>(null);
   const [isModalOpen, setIsModalOpen] = useState(false);
   const [togglingGateway, setTogglingGateway] = useState<string | null>(null);
+  const isDesktop = useMediaQuery("(min-width: 768px)");
 
   // Fetch all payment gateways
   const { data: gateways = [], isLoading, refetch } = useQuery({
@@ -261,10 +264,10 @@ export default function PaymentsPage() {
         )}
       </SettingsLayout>
 
-      {/* Gateway Settings Modal */}
-      {selectedGateway && (
+      {/* Gateway Settings Modal - Responsive: Dialog on desktop, Drawer on mobile */}
+      {selectedGateway && isDesktop && (
         <Dialog open={isModalOpen} onOpenChange={setIsModalOpen}>
-          <DialogContent className="max-w-2xl max-h-[100vh] flex flex-col p-0 gap-0">
+          <DialogContent className="max-w-2xl max-h-[80vh] flex flex-col p-0 gap-0">
             <DialogHeader className="px-6 pt-6 pb-4 border-b shrink-0">
               <DialogTitle>{selectedGateway.title} Settings</DialogTitle>
             </DialogHeader>
@@ -277,22 +280,20 @@ export default function PaymentsPage() {
               />
             </div>
             {/* Footer outside scrollable area */}
-            <div className="border-t px-4 sm:px-6 py-3 sm:py-4 flex flex-col sm:flex-row items-stretch sm:items-center gap-2 sm:gap-0 sm:justify-between shrink-0 bg-background sm:rounded-b-lg">
+            <div className="border-t px-6 py-4 flex items-center justify-between shrink-0 bg-background rounded-b-lg">
               <Button
                 type="button"
                 variant="outline"
                 onClick={() => setIsModalOpen(false)}
                 disabled={saveMutation.isPending}
-                className="order-3 sm:order-1"
               >
                 Cancel
               </Button>
-              <div className="flex flex-col sm:flex-row items-stretch sm:items-center gap-2 order-1 sm:order-2">
+              <div className="flex items-center gap-2">
                 <Button
                   type="button"
                   variant="ghost"
                   asChild
-                  className="justify-center"
                 >
                   <a
                     href={selectedGateway.wc_settings_url}
@@ -310,7 +311,6 @@ export default function PaymentsPage() {
                     if (form) form.requestSubmit();
                   }}
                   disabled={saveMutation.isPending}
-                  className="order-1 sm:order-2"
                 >
                   {saveMutation.isPending ? 'Saving...' : 'Save Settings'}
                 </Button>
@@ -319,6 +319,62 @@ export default function PaymentsPage() {
           </DialogContent>
         </Dialog>
       )}
+
+      {selectedGateway && !isDesktop && (
+        <Drawer open={isModalOpen} onOpenChange={setIsModalOpen}>
+          <DrawerContent className="max-h-[90vh] flex flex-col">
+            <DrawerHeader className="border-b shrink-0">
+              <DrawerTitle>{selectedGateway.title} Settings</DrawerTitle>
+            </DrawerHeader>
+            <div className="flex-1 overflow-y-auto px-4 py-6 min-h-0">
+              <GenericGatewayForm
+                gateway={selectedGateway}
+                onSave={handleSaveGateway}
+                onCancel={() => setIsModalOpen(false)}
+                hideFooter
+              />
+            </div>
+            {/* Footer outside scrollable area */}
+            <div className="border-t px-4 py-3 flex flex-col gap-2 shrink-0 bg-background">
+              <Button 
+                onClick={() => {
+                  const form = document.querySelector('form');
+                  if (form) form.requestSubmit();
+                }}
+                disabled={saveMutation.isPending}
+                className="w-full"
+              >
+                {saveMutation.isPending ? 'Saving...' : 'Save Settings'}
+              </Button>
+              <Button
+                type="button"
+                variant="ghost"
+                asChild
+                className="w-full"
+              >
+                <a
+                  href={selectedGateway.wc_settings_url}
+                  target="_blank"
+                  rel="noopener noreferrer"
+                  className="inline-flex items-center justify-center gap-1"
+                >
+                  View in WooCommerce
+                  <ExternalLink className="h-4 w-4" />
+                </a>
+              </Button>
+              <Button
+                type="button"
+                variant="outline"
+                onClick={() => setIsModalOpen(false)}
+                disabled={saveMutation.isPending}
+                className="w-full"
+              >
+                Cancel
+              </Button>
+            </div>
+          </DrawerContent>
+        </Drawer>
+      )}
     </>
   );
 }