feat: add JS-015 architecture rule to enforce confirm_modal over native confirm()

Prevents reintroduction of native browser confirm() dialogs by flagging
them as architecture errors during pre-commit validation. Points
developers to use confirm_modal/confirm_modal_dynamic Jinja2 macros.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.architecture-rules/frontend.yaml

@@ -238,6 +238,50 @@ javascript_rules:
       exceptions:
         - "utils.js"
 
+  - id: "JS-015"
+    name: "Use confirm_modal macros, not native confirm()"
+    severity: "error"
+    description: |
+      All confirmation dialogs must use the project's confirm_modal or
+      confirm_modal_dynamic Jinja2 macros from shared/macros/modals.html.
+      Never use the native browser confirm() dialog.
+
+      The modal macros provide:
+      - Consistent styled dialogs matching the admin/store theme
+      - Dark mode support
+      - Variant colors (danger=red, warning=yellow, info=blue)
+      - Icon support
+      - Double-confirm pattern for destructive operations
+
+      WRONG (native browser dialog):
+        if (!confirm('Are you sure you want to delete this?')) return;
+        if (!confirm(I18n.t('confirmations.delete'))) return;
+
+      RIGHT (state variable + modal macro):
+        // In JS: add state variable and remove confirm() guard
+        showDeleteModal: false,
+        async deleteItem() {
+            // No confirm() guard — modal already confirmed
+            await apiClient.delete('/admin/items/' + this.item.id);
+        }
+
+        // In template: button sets state, macro shows modal
+        <button @click="showDeleteModal = true">Delete</button>
+        {{ confirm_modal('deleteModal', 'Delete Item', 'Are you sure?',
+           'deleteItem()', 'showDeleteModal', 'Delete', 'Cancel', 'danger') }}
+
+      For dynamic messages (containing JS expressions):
+        {{ confirm_modal_dynamic('deleteModal', 'Delete Item',
+           "'Delete ' + item.name + '?'",
+           'deleteItem()', 'showDeleteModal', 'Delete', 'Cancel', 'danger') }}
+    pattern:
+      file_pattern: "static/**/js/**/*.js"
+      anti_patterns:
+        - "confirm\\("
+      exceptions:
+        - "utils.js"
+        - "vendor/"
+
   - id: "JS-010"
     name: "Use PlatformSettings for pagination rows per page"
     severity: "error"