feat: icon-only toolbar, versioning fixes, history modal, PanelRight repositioning

- Toolbar: remove text labels from all icon buttons (AI, Save, Preview, Convert)
  all buttons now icon-only with title tooltip for accessibility
- Toolbar: reposition PanelRight (info panel toggle) to far right after three-dot menu
- Versioning: decouple getNoteHistory/restoreNoteVersion from global userAISettings.noteHistory
  now checks note.historyEnabled directly — unblocks manual per-note history
- Versioning: add 'Sauvegarder cette version' button in Versions tab of info panel
  calls commitNoteHistory with visual feedback (spinner → success state)
- note-document-info-panel: import commitNoteHistory, add isSavingVersion state
- notes.ts: fix double guard that silently blocked all history operations

memento-note/app/actions/ai-settings.ts

@@ -23,7 +23,7 @@ export type UserAISettingsData = {
   autoLabeling?: boolean
   noteHistory?: boolean
   noteHistoryMode?: 'manual' | 'auto'
-  fontFamily?: 'inter' | 'system'
+  fontFamily?: 'inter' | 'playfair' | 'jetbrains' | 'system'
 }
 
 /** Only fields that exist on `UserAISettings` in Prisma (excludes e.g. `theme`, which lives on `User`). */
@@ -191,7 +191,7 @@ const getCachedAISettings = unstable_cache(
         autoLabeling: settings.autoLabeling ?? true,
         noteHistory: settings.noteHistory ?? false,
         noteHistoryMode: (settings.noteHistoryMode ?? 'manual') as 'manual' | 'auto',
-        fontFamily: (settings.fontFamily || 'inter') as 'inter' | 'system',
+        fontFamily: (settings.fontFamily || 'inter') as 'inter' | 'playfair' | 'jetbrains' | 'system',
       }
     } catch (error) {
       console.error('Error getting AI settings:', error)