feat: Find & Replace dans l'éditeur (Ctrl+F) + corrections Toggle/Callout/Outline

- Find & Replace : barre flottante Ctrl+F, recherche instantanée synchrone
  - Highlights ProseMirror (jaune = match, orange = actif)
  - Scroll vers le match sans voler le focus de l'input
  - Options: sensible à la casse, regex
  - Remplacer / Tout remplacer
  - i18n FR/EN complet
- Toggle/Callout/Outline: corrections bugs + design

memento-note/locales/en.json

@@ -2416,6 +2416,17 @@
     "outlineTitle": "Outline",
     "outlineEmpty": "Add headings (H1, H2, H3) to generate the outline",
     "outlineDelete": "Delete outline",
+    "findReplaceTitle": "Find",
+    "findPlaceholder": "Find in note...",
+    "replacePlaceholder": "Replace with...",
+    "replace": "Replace",
+    "replaceAll": "Replace all",
+    "findNext": "Next match",
+    "findPrev": "Previous match",
+    "findCaseSensitive": "Case sensitive",
+    "findWholeWord": "Whole word",
+    "findRegex": "Regular expression",
+    "findReplaceToggle": "Show/Hide replace",
     "calloutDelete": "Delete callout",
     "calloutUnwrap": "Disable callout",
     "calloutInfo": "Information",