docs(excalidraw,roadmap): #78 H1-H3 doc utilisateur + #61/#74 optionnels non retenus

- README FR/EN : .excalidraw dans les formats supportes + section Diagrammes Excalidraw
- Guide integre : nouvelle section Excalidraw (i18n FR/EN) + note compatibilite plugin Obsidian
- ROADMAP : #78 termine (B5/F3/H1-H3), C8/F2 non retenus ; #61 et #74 optionnels marques non retenus
- CHANGELOG : entree Documentation

frontend/locales/en.json

@@ -1076,6 +1076,7 @@
   "help.nav_tips": "💡 Tips",
   "help.nav_webhooks": "🪝 Webhooks",
   "help.nav_plugins": "🧩 Plugins",
+  "help.nav_excalidraw": "🎨 Excalidraw",
   "help.new_file": "New file",
   "help.new_folder": "New folder",
   "help.nights": "sleepless nights 😅",
@@ -1668,5 +1669,15 @@
       "help.plugins_security_3": "Secure packaging: the .zip is checked against path traversal on install.",
       "help.plugins_security_4": "Admin only: installation and removal require the admin role.",
       "help.plugins_template": "Use the <strong>Template</strong> button in Settings > Plugins to generate a valid starter plugin.",
+      "help.excalidraw_title": "🎨 Excalidraw diagrams",
+      "help.excalidraw_intro": "<code>.excalidraw</code> and <code>.excalidraw.md</code> files open in a full visual Excalidraw editor embedded in a sandboxed iframe.",
+      "help.excalidraw_open_title": "Opening",
+      "help.excalidraw_open": "Click a <code>.excalidraw</code> file in the tree: the editor opens instead of the markdown viewer.",
+      "help.excalidraw_edit": "Draw, add shapes, text, arrows and images — the complete Excalidraw experience.",
+      "help.excalidraw_save_title": "Saving",
+      "help.excalidraw_save": "Changes are saved automatically (2s debounce) or with <strong>Ctrl+S</strong>. The editor follows the light/dark theme.",
+      "help.excalidraw_search_title": "Search",
+      "help.excalidraw_search": "Text inside diagram elements is extracted on indexing, so it is searchable via the full-text search.",
+      "help.excalidraw_compat": "Files created with the Obsidian Excalidraw plugin (including the compressed <code>.excalidraw.md</code> format) are compatible.",
       "help.footer_tagline": "- Web gateway for your Obsidian vaults"
   }

frontend/locales/fr.json

@@ -1076,6 +1076,7 @@
   "help.nav_tips": "💡 Astuces",
   "help.nav_webhooks": "🪝 Webhooks",
   "help.nav_plugins": "🧩 Plugins",
+  "help.nav_excalidraw": "🎨 Excalidraw",
   "help.new_file": "Nouveau fichier",
   "help.new_folder": "Nouveau dossier",
   "help.nights": "nuits blanches 😅",
@@ -1668,5 +1669,15 @@
     "help.plugins_security_3": "Empaquetage sécurisé : le .zip est vérifié contre le path traversal à l'installation.",
     "help.plugins_security_4": "Admin uniquement : l'installation et la suppression requièrent le rôle admin.",
     "help.plugins_template": "Utilisez le bouton <strong>Template</strong> dans Paramètres > Plugins pour générer un plugin starter valide.",
+    "help.excalidraw_title": "🎨 Diagrammes Excalidraw",
+    "help.excalidraw_intro": "Les fichiers <code>.excalidraw</code> et <code>.excalidraw.md</code> s'ouvrent dans un éditeur visuel Excalidraw complet, intégré dans une iframe sandboxée.",
+    "help.excalidraw_open_title": "Ouverture",
+    "help.excalidraw_open": "Cliquez sur un fichier <code>.excalidraw</code> dans l'arborescence : l'éditeur s'ouvre à la place du viewer markdown.",
+    "help.excalidraw_edit": "Dessinez, ajoutez des formes, du texte, des flèches et des images — l'expérience Excalidraw complète.",
+    "help.excalidraw_save_title": "Sauvegarde",
+    "help.excalidraw_save": "Les modifications sont sauvegardées automatiquement (2 s) ou avec <strong>Ctrl+S</strong>. L'éditeur suit le thème clair/sombre.",
+    "help.excalidraw_search_title": "Recherche",
+    "help.excalidraw_search": "Le texte des éléments du diagramme est extrait à l'indexation : il est donc recherchable via la recherche full-text.",
+    "help.excalidraw_compat": "Les fichiers créés avec le plugin Obsidian Excalidraw (y compris le format <code>.excalidraw.md</code> compressé) sont compatibles.",
     "help.footer_tagline": "- Porte d'entrée web pour vos vaults Obsidian"
   }