feat(dev_tools): add translation editor for browsing and editing UI translations

New admin page to browse, search, compare, and inline-edit translation
keys across all modules and languages from the browser.

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

app/modules/dev_tools/locales/fr.json

@@ -14,7 +14,24 @@
         "components": "Composants",
         "icons": "Icônes",
         "sql_query": "Requête SQL",
-        "platform_debug": "Debug Plateforme"
+        "platform_debug": "Debug Plateforme",
+        "translation_editor": "Éditeur de traductions"
+    },
+    "translation_editor": {
+        "title": "Éditeur de traductions",
+        "all_modules": "Tous les modules",
+        "search_placeholder": "Rechercher clés et valeurs...",
+        "filter_all": "Tous",
+        "filter_missing": "Manquantes",
+        "filter_variables": "Variables",
+        "module": "Module",
+        "key_path": "Chemin de clé",
+        "missing": "manquante",
+        "saving": "Enregistrement...",
+        "no_results": "Aucune clé de traduction ne correspond à vos filtres.",
+        "loading": "Chargement des traductions...",
+        "previous": "Précédent",
+        "next": "Suivant"
     },
     "sql_query": {
         "title": "Outil de requête SQL",