feat(114): accounting configs refactor + invoice configs CRUD

Phase 114 complete (v3.7 Invoices):
- /settings/accounting jako hub-rozdroze (Paragony / Faktury)
- /settings/accounting/receipts + /invoices osobne podstrony list i edycji
- InvoiceConfigRepository + Controller (CRUD z walidacja delegacji)
- Seed Domyslny VAT (NOT EXISTS idempotent)
- invoice-config-form.js (toggle is_delegated -> integration_id)
- confirm-delete.js (globalny modul OrderProAlerts.confirm)
- Legacy aliasy starych endpointow /settings/accounting/save|toggle|delete

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

public/assets/js/modules/invoice-config-form.js

@@ -0,0 +1,35 @@
+(function () {
+  'use strict';
+
+  function sync(checkbox, wrapper) {
+    if (!checkbox || !wrapper) return;
+    var select = wrapper.querySelector('select[name="integration_id"]');
+    if (checkbox.checked) {
+      wrapper.style.display = '';
+      if (select) select.required = true;
+    } else {
+      wrapper.style.display = 'none';
+      if (select) {
+        select.required = false;
+        select.value = '';
+      }
+    }
+  }
+
+  function init() {
+    var checkbox = document.querySelector('[data-invoice-delegated]');
+    var wrapper = document.querySelector('[data-invoice-delegation]');
+    if (!checkbox || !wrapper) return;
+
+    sync(checkbox, wrapper);
+    checkbox.addEventListener('change', function () {
+      sync(checkbox, wrapper);
+    });
+  }
+
+  if (document.readyState === 'loading') {
+    document.addEventListener('DOMContentLoaded', init);
+  } else {
+    init();
+  }
+})();