feat(admin): redesign order list and detail workspace

Replace the type/method tab rows with status views backed by one GROUP BY
count, move filters into a single toolbar card, show gateway names, keep
list context across detail and actions, and split the detail page into a
summary/timeline column and an actions/buyer/note sidebar. Confirmations
move to admin-orders.js; PayOrders splits into flat List/Detail traits.

Remove dead code: unused Order AJAX endpoints and init(), get_orders_count(),
shipping flash codes, and the legacy raw-note fallback.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

functions.php

@@ -316,9 +316,6 @@ if (class_exists('\AKSRT\Attachment\UploadLimits')) {
 if (class_exists('\AKSRT\Attachment\PendingUploads')) {
     \AKSRT\Attachment\PendingUploads::get_instance()->init();
 }
-if (class_exists('\AKSRT\Payment\Order')) {
-    \AKSRT\Payment\Order::get_instance()->init();
-}
 
 // Register built-in payment gateways
 if (class_exists('\AKSRT\Payment\Gateway')) {