Auto-save drafts to localStorage

- Drafts saved 1s after last keystroke (debounced)
- 'Draft saved' indicator in toolbar
- On file open: prompts to restore unsaved draft if found
- Draft cleared on successful save (Ctrl+S)
- Works across disconnects/logouts — draft persists in browser

frontend/src/App.vue

@@ -74,6 +74,7 @@
         </div>
         <div class="toolbar-right">
           <span class="file-name">{{ currentFile || 'No file open' }}</span>
+          <span v-if="draftSaved" class="draft-indicator">Draft saved</span>
           <span class="file-meta" v-if="fileMeta">{{ fileMeta }}</span>
           <button v-if="currentFile" class="toolbar-btn" @click="toggleCollab" :title="collabActive ? 'Disconnect collab' : 'Enable collab'">
             {{ collabActive ? '👥 Live' : '👤 Solo' }}
@@ -99,7 +100,7 @@
           <textarea
             ref="editor"
             v-model="content"
-            @input="isDirty = true"
+            @input="onEdit"
             @keydown="handleKeydown"
             @drop.prevent="handleImageDrop"
             @dragover.prevent
@@ -110,7 +111,7 @@
           <MilkdownEditor
             :key="currentFile"
             v-model="content"
-            @update:modelValue="isDirty = true"
+            @update:modelValue="onEdit"
           />
         </div>
         <div v-if="mode === 'split'" class="preview-pane">
@@ -514,14 +515,53 @@ async function openFile(path) {
     }
   }
   isDirty.value = false
+  draftSaved.value = false
   view.value = 'files'
   showHistory.value = false
   showShareDialog.value = false
   aiResult.value = ''
+
+  // Check for unsaved draft
+  const draft = loadDraft()
+  if (draft && draft !== content.value) {
+    if (confirm('You have an unsaved draft for this file. Restore it?')) {
+      content.value = draft
+      isDirty.value = true
+    } else {
+      clearDraft()
+    }
+  }
   loadHistory()
   checkGitStatus()
 }
 
+// ─── Auto-draft ──────────────────────────────────────────────────────────────
+
+const draftSaved = ref(false)
+let draftTimer = null
+
+function onEdit() {
+  isDirty.value = true
+  draftSaved.value = false
+  clearTimeout(draftTimer)
+  draftTimer = setTimeout(() => {
+    const key = currentFile.value || '_unsaved'
+    localStorage.setItem('mh_draft_' + key, content.value)
+    draftSaved.value = true
+  }, 1000)
+}
+
+function clearDraft() {
+  const key = currentFile.value || '_unsaved'
+  localStorage.removeItem('mh_draft_' + key)
+  draftSaved.value = false
+}
+
+function loadDraft() {
+  const key = currentFile.value || '_unsaved'
+  return localStorage.getItem('mh_draft_' + key)
+}
+
 async function saveFile() {
   if (!currentFile.value) {
     const name = prompt('Save as (e.g. notes.md):')
@@ -551,6 +591,7 @@ async function saveFile() {
   }
   cacheFile(currentFile.value, content.value)
   isDirty.value = false
+  clearDraft()
   setTimeout(checkGitStatus, 1000)
 }
 
@@ -1200,6 +1241,7 @@ body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; b
 }
 
 .file-name { color: var(--text-muted); font-size: 13px; }
+.draft-indicator { color: var(--success); font-size: 11px; opacity: 0.8; }
 
 .export-actions { display: flex; gap: 4px; }
 .export-actions button {