feat(mobile): editeur mobile natif - interface tactile optimisee (#69)

Barre d'outils Markdown flottante (gras/italique/code/liste/lien) sur la selection CodeMirror, bouton Coller persistant (contournement iOS), zoom par pincement + hauteur ajustable persistes, raccourcis swipe (gauche -> liens entrants, droite -> table des matieres), mode lecture plein ecran avec navigation entre fichiers du dossier. 22 tests JSDOM + spec E2E mobile. Docs: fiche feature, CHANGELOG, ROADMAP, guide i18n FR/EN, README.

frontend/locales/en.json

@@ -1095,6 +1095,18 @@
   "help.mermaid_section": "Mermaid diagrams",
   "help.mermaid_templates": "Templates",
   "help.mobile": "Floating results bar",
+  "help.mobile_editor_gestures": ": swipe left → backlinks, swipe right → table of contents.",
+  "help.mobile_editor_gestures_label": "Touch gestures",
+  "help.mobile_editor_intro": "On phones and tablets, editing adapts to touch: floating toolbar, gestures and a full-screen reading mode.",
+  "help.mobile_editor_paste": ": persistent “Paste” button (works around the iOS restriction).",
+  "help.mobile_editor_paste_label": "Clipboard",
+  "help.mobile_editor_reading": ": full screen without header or sidebars; swipe horizontally to go to the next or previous file.",
+  "help.mobile_editor_reading_label": "Reading mode",
+  "help.mobile_editor_title": "📱 Mobile editing",
+  "help.mobile_editor_toolbar": ": bold, italic, code, bullet list and link. The A−/A+ buttons adjust the font size.",
+  "help.mobile_editor_toolbar_label": "Floating toolbar",
+  "help.mobile_editor_zoom": ": pinch with two fingers to zoom, drag the handle to resize the editing area.",
+  "help.mobile_editor_zoom_label": "Zoom & height",
   "help.modal_title": "ObsiGate User Guide",
   "help.multi_vault": "Multi-vault",
   "help.nav_ai": "🤖 AI Editor",
@@ -1105,6 +1117,7 @@
   "help.nav_graph": "🗺️ Graph",
   "help.nav_interface": "🧭 Interface",
   "help.nav_intro": "📘 Introduction",
+  "help.nav_mobile_editor": "📱 Mobile",
   "help.nav_navigation": "🗺️ Navigation",
   "help.nav_palette": "⌨️ Palette",
   "help.nav_search": "🔍 Search",
@@ -1250,6 +1263,28 @@
   "mermaid.zoom_in": "Zoom in",
   "mermaid.zoom_out": "Zoom out",
   "mobile.all_vaults": "📂 All vaults",
+  "mobile_editor.backlinks": "Backlinks",
+  "mobile_editor.bold": "Bold",
+  "mobile_editor.close": "Close",
+  "mobile_editor.code": "Code",
+  "mobile_editor.error": "Loading error",
+  "mobile_editor.font_larger": "Increase font size",
+  "mobile_editor.font_smaller": "Decrease font size",
+  "mobile_editor.italic": "Italic",
+  "mobile_editor.link": "Link",
+  "mobile_editor.list": "Bullet list",
+  "mobile_editor.loading": "Loading…",
+  "mobile_editor.no_backlinks": "No backlinks",
+  "mobile_editor.no_headings": "No headings in this document",
+  "mobile_editor.no_next": "Last file in folder",
+  "mobile_editor.no_prev": "First file in folder",
+  "mobile_editor.paste": "Paste",
+  "mobile_editor.paste_hint": "Long-press the field then choose “Paste” (clipboard access denied).",
+  "mobile_editor.reading_enter": "Reading mode",
+  "mobile_editor.reading_exit": "Exit reading mode",
+  "mobile_editor.resize": "Adjust editor height",
+  "mobile_editor.toc": "Table of contents",
+  "mobile_editor.toolbar": "Mobile editing toolbar",
   "modal.create_btn": "Create",
   "modal.create_file": "Create a file",
   "modal.creating": "Creating...",