feat: mobile app complet + flashcards fixes + drag handle améliorations

Mobile app:
- Révision flashcards : liste decks, session flip-card SM-2, couleurs harmonisées web
- Génération flashcards depuis note (FlashcardSheet + route /api/mobile/flashcards/generate)
- Audio Whisper : hook useAudioRecorder reécrit, MicButton avec erreurs
- IA : AISheet (améliorer/clarifier/résumer), TitleSheet (titre automatique)
- Suppression note (soft delete + confirmation Alert)
- Note du jour : titre lisible + HTML (plus JSON TipTap brut)
- Parser TipTap→HTML côté mobile (tipTapToHtml)
- Icône 🎓 dans header note → génération flashcards
- Endpoint flashcardGenerate dans config.ts

Web fixes:
- Bug flashcards groupées par carnet → deck par note (migration + schema)
- Bug filtre 'cartes dues' ignoré (suppression fallback buildSessionQueue)
- Suppression UI création deck manuelle (inutile)
- Fix setViewType is not defined dans home-client.tsx

Drag handle menu:
- Fix : clearNodes() avant transformation (heading→liste/code/citation)
- Ajout : option 'Texte' (paragraphe) dans Transformer en
- Ajout : Monter / Descendre le bloc
- Ajout : Copier le contenu du bloc
- Fix : sous-menu hover stable (délai 200ms)
- Fix : Supprimer en rouge via classe --danger (plus :first-child)
- i18n : nouvelles clés dans 15 locales

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

memento-note/locales/ru.json

@@ -2867,5 +2867,32 @@
     "hint_insights_bridge_desc": "Bridge notes connect multiple clusters. They are highlighted because they hold your knowledge graph together.",
     "hint_insights_refresh_title": "Refresh clusters",
     "hint_insights_refresh_desc": "If you've added new notes, click the refresh button to recalculate the clusters with the latest content."
+  },
+  "blockAction": {
+    "moveUp": "Move block up",
+    "moveDown": "Move block down",
+    "moveUpFirst": "This is already the first block",
+    "moveDownLast": "This is already the last block",
+    "copyContent": "Copy content",
+    "contentCopied": "Content copied!",
+    "emptyBlock": "This block is empty",
+    "turnInto_paragraph": "Text",
+    "delete": "Delete",
+    "duplicate": "Duplicate",
+    "turnInto": "Turn into",
+    "turnInto_heading1": "Heading 1",
+    "turnInto_heading2": "Heading 2",
+    "turnInto_heading3": "Heading 3",
+    "turnInto_bulletList": "Bullet List",
+    "turnInto_orderedList": "Numbered List",
+    "turnInto_taskList": "Task List",
+    "turnInto_blockquote": "Quote",
+    "turnInto_codeBlock": "Code Block",
+    "turnInto_database": "Inline database",
+    "copyRef": "Copy block reference",
+    "copied": "Reference copied!",
+    "copyRefFailed": "Could not copy block reference",
+    "copyRefNoNote": "Save the note before copying a block reference",
+    "copyRefUnsupported": "This block type cannot be referenced yet"
   }
 }