fix: Modal initial values + sticky footer + HTML descriptions

✅ Issue 1: Modal Not Showing Current Values (FIXED!)
Problem: Opening modal showed defaults, not current saved values
Root Cause: Backend only sent field.default, not current value
Solution:
- Backend: Added field.value with current saved value
- normalize_field() now includes: value: $current_settings[$key]
- Frontend: Use field.value ?? field.default for initial data
- GenericGatewayForm initializes with current values

Result: ✅ Modal now shows "BNI Virtual Account 2" not "BNI Virtual Account"

✅ Issue 2: Sticky Modal Footer (FIXED!)
Problem: Footer scrolls away with long forms
Solution:
- Restructured modal: header + scrollable body + sticky footer
- DialogContent: flex flex-col with overflow on body only
- Footer: sticky bottom-0 with border-t
- Save button triggers form.requestSubmit()

Result: ✅ Cancel, View in WooCommerce, Save always visible

✅ Issue 3: HTML in Descriptions (FIXED!)
Problem: TriPay icon shows as raw HTML string
Solution:
- Changed: {field.description}
- To: dangerouslySetInnerHTML={{ __html: field.description }}
- Respects vendor creativity (images, formatting, links)

Result: ✅ TriPay icon image renders properly

📋 Technical Details:

Backend Changes (PaymentGatewaysProvider.php):
- get_gateway_settings() passes $current_settings to extractors
- normalize_field() adds 'value' => $current_settings[$key]
- All fields now have both default and current value

Frontend Changes:
- GatewayField interface: Added value?: string | boolean
- GenericGatewayForm: Initialize with field.value
- Modal structure: Header + Body (scroll) + Footer (sticky)
- Descriptions: Render as HTML with dangerouslySetInnerHTML

Files Modified:
- PaymentGatewaysProvider.php: Add current values to fields
- Payments.tsx: Restructure modal layout + add value to interface
- GenericGatewayForm.tsx: Use field.value + sticky footer + HTML descriptions

🎯 Result:
✅ Modal shows current saved values
✅ Footer always visible (no scrolling)
✅ Vendor HTML/images render properly

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

@@ -18,6 +18,7 @@ interface GatewayField {
   title: string;
   description: string;
   default: string | boolean;
+  value: string | boolean;  // Current saved value
   placeholder?: string;
   required: boolean;
   options?: Record<string, string>;
@@ -327,15 +328,17 @@ export default function PaymentsPage() {
       {/* Gateway Settings Modal */}
       {selectedGateway && (
         <Dialog open={isModalOpen} onOpenChange={setIsModalOpen}>
-          <DialogContent className="max-w-2xl max-h-[80vh] overflow-y-auto">
-            <DialogHeader>
+          <DialogContent className="max-w-2xl max-h-[80vh] flex flex-col p-0">
+            <DialogHeader className="px-6 pt-6 pb-4 border-b">
               <DialogTitle>{selectedGateway.title} Settings</DialogTitle>
             </DialogHeader>
-            <GenericGatewayForm
-              gateway={selectedGateway}
-              onSave={handleSaveGateway}
-              onCancel={() => setIsModalOpen(false)}
-            />
+            <div className="flex-1 overflow-y-auto px-6 py-4">
+              <GenericGatewayForm
+                gateway={selectedGateway}
+                onSave={handleSaveGateway}
+                onCancel={() => setIsModalOpen(false)}
+              />
+            </div>
           </DialogContent>
         </Dialog>
       )}