feat: indicateur versioning sur cartes + toolbar éditeur

Note card:
- Icône History en overlay bottom-right (visible si historyEnabled=true)
- Discrète: text-muted-foreground/50, ne pollue pas l'UI
- Tooltip 'Historique des versions activé'

Toolbar éditeur:
- Icône History à côté du statut Saved/Dirty
- Visible seulement en sm+ (desktop)
- cursor-help + tooltip

i18n:
- notes.historyEnabledTooltip ajouté aux 15 locales (FR/EN traduits, 13 EN placeholder)

memento-note/locales/ar.json

@@ -282,7 +282,8 @@
     "unarchived": "إلغاء الأرشفة",
     "uploading": "جاري الرفع...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/de.json

@@ -282,7 +282,8 @@
     "unarchived": "Entarchiviert",
     "uploading": "Wird hochgeladen...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/en.json

@@ -315,7 +315,8 @@
     "createFirst": "Create your first note",
     "unarchived": "Unarchived",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/es.json

@@ -282,7 +282,8 @@
     "unarchived": "Desarchivado",
     "uploading": "Subiendo...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/fa.json

@@ -282,7 +282,8 @@
     "unarchived": "خارج بایگانی",
     "uploading": "در حال آپلود...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/fr.json

@@ -321,7 +321,8 @@
     "createFirst": "Créez votre première note",
     "unarchived": "Désarchivée",
     "savedJustNow": "Sauvegardé",
-    "unsaved": "Non sauvegardé"
+    "unsaved": "Non sauvegardé",
+    "historyEnabledTooltip": "Historique des versions activé — les modifications sont suivies"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/hi.json

@@ -282,7 +282,8 @@
     "unarchived": "अनार्काइव नहीं",
     "uploading": "अपलोड हो रहा है...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/it.json

@@ -282,7 +282,8 @@
     "unarchived": "Dearchiviato",
     "uploading": "Caricamento...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/ja.json

@@ -282,7 +282,8 @@
     "unarchived": "アーカイブ解除",
     "uploading": "アップロード中...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/ko.json

@@ -282,7 +282,8 @@
     "unarchived": "보관 해제됨",
     "uploading": "업로드 중...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/nl.json

@@ -282,7 +282,8 @@
     "unarchived": "Gearchiveerd",
     "uploading": "Uploaden...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/pl.json

@@ -282,7 +282,8 @@
     "unarchived": "Wycofane z archiwum",
     "uploading": "Przesyłanie...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/pt.json

@@ -282,7 +282,8 @@
     "unarchived": "Desarquivado",
     "uploading": "Enviando...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/ru.json

@@ -282,7 +282,8 @@
     "unarchived": "Разархивировано",
     "uploading": "Загрузка...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",

memento-note/locales/zh.json

@@ -282,7 +282,8 @@
     "unarchived": "已取消归档",
     "uploading": "上传中...",
     "savedJustNow": "Saved",
-    "unsaved": "Unsaved changes"
+    "unsaved": "Unsaved changes",
+    "historyEnabledTooltip": "Version history enabled — changes are tracked"
   },
   "pagination": {
     "previous": "←",