feat: add backup file management settings

- Added settings UI to enable/disable .bak file creation when saving files
- Created settings storage in .obsidian/obsiviewer.json to persist backup preferences
- Added API endpoints to read/write backup settings (/api/settings)
- Implemented automatic cleanup of existing .bak files when disabling backups
- Modified file save operations to respect backup setting across notes, bookmarks and graph files
- Removed existing .bak files from version control

vault/.obsidian/bookmarks.json.bak

@@ -1,24 +0,0 @@
-{
-  "items": [
-    {
-      "type": "group",
-      "ctime": 1759433919563,
-      "title": "test",
-      "items": [
-        {
-          "type": "file",
-          "ctime": 1759433952208,
-          "path": "HOME.md",
-          "title": "HOME"
-        }
-      ]
-    },
-    {
-      "type": "file",
-      "ctime": 1759434060575,
-      "path": "test.md",
-      "title": "Page de test Markdown"
-    }
-  ],
-  "rev": "9mgl-40"
-}

vault/.obsidian/graph.json.bak

@@ -1,22 +0,0 @@
-{
-  "collapse-filter": false,
-  "search": "",
-  "showTags": false,
-  "showAttachments": false,
-  "hideUnresolved": false,
-  "showOrphans": true,
-  "collapse-color-groups": false,
-  "colorGroups": [],
-  "collapse-display": false,
-  "showArrow": false,
-  "textFadeMultiplier": 0,
-  "nodeSizeMultiplier": 1,
-  "lineSizeMultiplier": 1,
-  "collapse-forces": false,
-  "centerStrength": 0.3,
-  "repelStrength": 17,
-  "linkStrength": 0.5,
-  "linkDistance": 200,
-  "scale": 1,
-  "close": false
-}

vault/.obsidian/obsiviewer.json

@@ -0,0 +1,3 @@
+{
+  "enableBackups": false
+}

vault/.obsidian/workspace.json

@@ -178,10 +178,10 @@
   },
   "active": "8309e5042a8fb85c",
   "lastOpenFiles": [
+    "dessin.excalidraw.md",
     "Dessin-02.png",
     "mixe/Relaxing Music relax music music _hls-480_.mp4",
     "Dessin-02.excalidraw.md",
-    "dessin.excalidraw.md",
     "Drawing-20251028-1452.excalidraw.md",
     "Dessin-02.excalidraw.md.tmp",
     "Dessin-02.excalidraw.md.bak",