feat(orders): Dynamic shipping fields from checkout API

## Complete Rewrite of Shipping Implementation

### Backend (Already Done):
- ✅ `/checkout/fields` API endpoint
- ✅ Respects addon hide/show logic
- ✅ Handles digital-only products
- ✅ Returns field metadata (type, required, hidden, options, etc.)

### Frontend (New Implementation):
**Replaced hardcoded shipping fields with dynamic API-driven rendering**

#### Changes in OrderForm.tsx:

1. **Query checkout fields API:**
   - Fetches fields based on cart items
   - Enabled only when items exist
   - Passes product IDs and quantities

2. **Dynamic state management:**
   - Removed individual useState for each field (sFirst, sLast, sAddr1, etc.)
   - Replaced with single `shippingData` object: `Record<string, any>`
   - Cleaner, more flexible state management

3. **Dynamic field rendering:**
   - Filters fields by fieldset === 'shipping' and !hidden
   - Sorts by priority
   - Renders based on field.type:
     - `select` → Select with options
     - `country` → SearchableSelect
     - `textarea` → Textarea
     - default → Input (text/email/tel)
   - Respects required flag with visual indicator
   - Auto-detects wide fields (address_1, address_2)

4. **Form submission:**
   - Uses `shippingData` directly instead of individual fields
   - Cleaner payload construction

### Benefits:
- ✅ Addons can add custom fields (e.g., subdistrict)
- ✅ Fields show/hide based on addon logic
- ✅ Required flags respected
- ✅ Digital products hide shipping correctly
- ✅ No hardcoding - fully extensible
- ✅ Maintains existing UX

### Testing:
- Test with physical products → shipping fields appear
- Test with digital products → shipping hidden
- Test with addons that add fields → custom fields render
- Test form submission → data sent correctly

admin-spa/src/routes/Orders/partials/OrderForm.tsx

@@ -133,15 +133,9 @@ export default function OrderForm({
   const [bCountry, setBCountry] = React.useState(initial?.billing?.country || baseCountry);
   const [bState, setBState] = React.useState(initial?.billing?.state || '');
 
-  // Shipping toggle + fields
+  // Shipping toggle + dynamic fields
   const [shipDiff, setShipDiff] = React.useState(Boolean(initial?.shipping && !isEmptyAddress(initial?.shipping)));
-  const [sFirst, setSFirst] = React.useState(initial?.shipping?.first_name || '');
+  const [shippingData, setShippingData] = React.useState<Record<string, any>>(initial?.shipping || {});
-  const [sLast, setSLast] = React.useState(initial?.shipping?.last_name || '');
-  const [sAddr1, setSAddr1] = React.useState(initial?.shipping?.address_1 || '');
-  const [sCity, setSCity] = React.useState(initial?.shipping?.city || '');
-  const [sPost, setSPost] = React.useState(initial?.shipping?.postcode || '');
-  const [sCountry, setSCountry] = React.useState(initial?.shipping?.country || bCountry);
-  const [sState, setSState] = React.useState(initial?.shipping?.state || '');
 
   // If store sells to a single country, force-select it for billing & shipping
   React.useEffect(() => {
@@ -177,6 +171,18 @@ export default function OrderForm({
   const [validatedCoupons, setValidatedCoupons] = React.useState<any[]>([]);
   const [couponValidating, setCouponValidating] = React.useState(false);
 
+  // Fetch dynamic checkout fields based on cart items
+  const { data: checkoutFields } = useQuery({
+    queryKey: ['checkout-fields', items.map(i => ({ product_id: i.product_id, qty: i.qty }))],
+    queryFn: async () => {
+      if (items.length === 0) return null;
+      return api.post('/checkout/fields', {
+        items: items.map(i => ({ product_id: i.product_id, qty: i.qty })),
+      });
+    },
+    enabled: items.length > 0,
+  });
+
   // --- Product search for Add Item ---
   const [searchQ, setSearchQ] = React.useState('');
   const [customerSearchQ, setCustomerSearchQ] = React.useState('');
@@ -324,15 +330,7 @@ export default function OrderForm({
     const payload: OrderPayload = {
       status,
       billing: billingData,
-      shipping: shipDiff && hasPhysicalProduct ? {
+      shipping: shipDiff && hasPhysicalProduct ? shippingData : undefined,
-        first_name: sFirst,
-        last_name: sLast,
-        address_1: sAddr1,
-        city: sCity,
-        state: sState,
-        postcode: sPost,
-        country: sCountry,
-      } : undefined,
       payment_method: paymentMethod || undefined,
       shipping_method: shippingMethod || undefined,
       customer_note: note || undefined,
@@ -803,54 +801,65 @@ export default function OrderForm({
           </div>
         )}
 
-        {/* Shipping address */}
+        {/* Shipping address - Dynamic Fields */}
-        {hasPhysicalProduct && shipDiff && (
+        {hasPhysicalProduct && shipDiff && checkoutFields?.fields && (
           <div className="rounded border p-4 space-y-3 mt-4">
             <h3 className="text-sm font-medium">{__('Shipping address')}</h3>
             <div className="grid grid-cols-1 md:grid-cols-2 gap-3">
-              <div>
+              {checkoutFields.fields
-                <Label>{__('First name')}</Label>
+                .filter((f: any) => f.fieldset === 'shipping' && !f.hidden)
-                <Input className="rounded-md border px-3 py-2" value={sFirst} onChange={e=>setSFirst(e.target.value)} />
+                .sort((a: any, b: any) => (a.priority || 0) - (b.priority || 0))
-              </div>
+                .map((field: any) => {
-              <div>
+                  const isWide = ['address_1', 'address_2'].includes(field.key.replace('shipping_', ''));
-                <Label>{__('Last name')}</Label>
+                  const fieldKey = field.key.replace('shipping_', '');
-                <Input className="rounded-md border px-3 py-2" value={sLast} onChange={e=>setSLast(e.target.value)} />
+                  
-              </div>
+                  return (
-              <div className="md:col-span-2">
+                    <div key={field.key} className={isWide ? 'md:col-span-2' : ''}>
-                <Label>{__('Address')}</Label>
+                      <Label>
-                <Input className="rounded-md border px-3 py-2" value={sAddr1} onChange={e=>setSAddr1(e.target.value)} />
+                        {field.label}
-              </div>
+                        {field.required && <span className="text-destructive ml-1">*</span>}
-              <div>
+                      </Label>
-                <Label>{__('City')}</Label>
+                      {field.type === 'select' && field.options ? (
-                <Input className="rounded-md border px-3 py-2" value={sCity} onChange={e=>setSCity(e.target.value)} />
+                        <Select 
-              </div>
+                          value={shippingData[fieldKey] || ''} 
-              <div>
+                          onValueChange={(v) => setShippingData({...shippingData, [fieldKey]: v})}
-                <Label>{__('Postcode')}</Label>
+                        >
-                <Input className="rounded-md border px-3 py-2" value={sPost} onChange={e=>setSPost(e.target.value)} />
+                          <SelectTrigger className="w-full">
-              </div>
+                            <SelectValue placeholder={field.placeholder || field.label} />
-              <div>
+                          </SelectTrigger>
-                <Label>{__('Country')}</Label>
-                <SearchableSelect
-                  options={countryOptions}
-                  value={sCountry}
-                  onChange={setSCountry}
-                  placeholder={countries.length ? __('Select country') : __('No countries')}
-                  disabled={oneCountryOnly}
-                />
-              </div>
-              <div>
-                <Label>{__('State/Province')}</Label>
-                <Select value={sState} onValueChange={setSState}>
-                  <SelectTrigger className="w-full"><SelectValue placeholder={__('Select state')} /></SelectTrigger>
                           <SelectContent className="max-h-64">
-                    {sStateOptions.length ? sStateOptions.map(o => (
+                            {Object.entries(field.options).map(([value, label]: [string, any]) => (
-                      <SelectItem key={o.value} value={o.value}>{o.label}</SelectItem>
+                              <SelectItem key={value} value={value}>{label}</SelectItem>
-                    )) : (
+                            ))}
-                      <SelectItem value="__none__" disabled>{__('N/A')}</SelectItem>
-                    )}
                           </SelectContent>
                         </Select>
+                      ) : field.key === 'shipping_country' ? (
+                        <SearchableSelect
+                          options={countryOptions}
+                          value={shippingData.country || ''}
+                          onChange={(v) => setShippingData({...shippingData, country: v})}
+                          placeholder={field.placeholder || __('Select country')}
+                          disabled={oneCountryOnly}
+                        />
+                      ) : field.type === 'textarea' ? (
+                        <Textarea
+                          value={shippingData[fieldKey] || ''}
+                          onChange={(e) => setShippingData({...shippingData, [fieldKey]: e.target.value})}
+                          placeholder={field.placeholder}
+                          required={field.required}
+                        />
+                      ) : (
+                        <Input
+                          type={field.type === 'email' ? 'email' : field.type === 'tel' ? 'tel' : 'text'}
+                          value={shippingData[fieldKey] || ''}
+                          onChange={(e) => setShippingData({...shippingData, [fieldKey]: e.target.value})}
+                          placeholder={field.placeholder}
+                          required={field.required}
+                        />
+                      )}
                     </div>
+                  );
+                })}
             </div>
           </div>
         )}