feat(roles): add admin store roles page, permission i18n, and menu integration

- Add admin store roles page with merchant→store cascading for superadmin
  and store-only selection for platform admin
- Add permission catalog API with translated labels/descriptions (en/fr/de/lb)
- Add permission translations to all 15 module locale files (60 files total)
- Add info icon tooltips for permission descriptions in role editor
- Add store roles menu item and admin menu item in module definition
- Fix store-selector.js URL construction bug when apiEndpoint has query params
- Add admin store roles API (CRUD + platform scoping)
- Add integration tests for admin store roles and permission catalog

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

app/modules/inventory/locales/de.json

@@ -42,5 +42,13 @@
         "products_inventory": "Produkte & Inventar",
         "products": "Produkte",
         "inventory": "Inventar"
+    },
+    "permissions": {
+        "stock_view": "Inventar anzeigen",
+        "stock_view_desc": "Bestände und Inventardaten anzeigen",
+        "stock_edit": "Inventar bearbeiten",
+        "stock_edit_desc": "Bestände und Mengen anpassen",
+        "stock_transfer": "Bestand transferieren",
+        "stock_transfer_desc": "Bestand zwischen Standorten transferieren"
     }
 }