release: v0.4.0 — MetonaEditor 集成与架构重构

feat(editor): 将 Milkdown/ProseMirror 替换为 @metona-team/metona-editor v0.1.3
  - 三模式视图 (edit/split/preview) 由编辑器内置工具栏切换
  - searchReplace + imagePaste 预设插件
  - unified/rehype 渲染管线通过 render 钩子集成
  - 主题双向同步 (应用暗色模式 ↔ 编辑器主题)

feat(toast): metona-toast 迁移为 @metona-team/metona-toast v2.0.1

refactor: 删除冗余组件与代码
  - 移除 SourceEditor、Preview、SearchReplace、EditorToolbar、useMilkdown
  - 移除 StatusBar 组件及状态栏扩展架构（编辑器内置底栏替代）
  - 移除 useSettings、useStatusBarItem、useStatusBarItems、statusBarStore
  - 移除 EditMode/PreviewMode/SourceMode 图标

refactor(ui): 简化布局
  - 工具栏移除模式切换按钮，新增自动保存开关
  - useKeyboard 移除 Ctrl+1/2/3/B/I 快捷键
  - Editor 三模式统一由 MetonaEditor 容器渲染

chore: 版本号 v0.3.13 → v0.4.0
docs: 全面更新 README/DESIGN/CONTRIBUTING/DEVSETUP

src/renderer/components/Sidebar/Sidebar.tsx

@@ -11,11 +11,14 @@ import { useAutoExpandDir } from '../../hooks/useAutoExpandDir'
 import { useActiveHeading } from '../../hooks/useActiveHeading'
 import { OutlinePanel, parseHeadings } from '../OutlinePanel'
 import type { Heading } from '../OutlinePanel'
-import { getEditorView, useEditorStore } from '../../stores/editorStore'
-import { TextSelection } from '@milkdown/prose/state'
+import { getMetonaEditor, useEditorStore } from '../../stores/editorStore'
 
 const norm = (p: string) => p.replace(/[/\\]+$/, '').replace(/\\/g, '/')
 
+function escapeRegex(s: string): string {
+  return s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
+}
+
 export const Sidebar = React.memo(function Sidebar() {
   const tabs = useTabStore(s => s.tabs)
   const activeTabId = useTabStore(s => s.activeTabId)
@@ -43,12 +46,11 @@ export const Sidebar = React.memo(function Sidebar() {
     return parseHeadings(activeTab.content)
   }, [activeTab?.content])
 
-  // D4: 追踪预览面板中的活跃标题
+  // D4: 追踪预览面板中的活跃标题（适配 MetonaEditor 的 .me-preview）
   const previewRef = useRef<HTMLElement | null>(null)
   useEffect(() => {
-    // 仅在预览模式时获取 preview DOM 节点
     if (viewMode === 'preview') {
-      previewRef.current = document.getElementById('preview')
+      previewRef.current = document.querySelector('.me-preview') as HTMLElement | null
     } else {
       previewRef.current = null
     }
@@ -59,37 +61,40 @@ export const Sidebar = React.memo(function Sidebar() {
     headings
   )
 
-  // Navigate to heading in ProseMirror document tree
-  const handleHeadingNavigate = useCallback((heading: Heading, index: number) => {
-    const view = getEditorView()
-    if (!view) return
+  // Navigate to heading in MetonaEditor
+  const handleHeadingNavigate = useCallback((heading: Heading) => {
+    const editor = getMetonaEditor()
+    if (!editor) return
+
     try {
-      let foundPos: number | null = null
-      let currentIndex = 0
+      // 获取当前内容，查找标题文本在源代码中的位置
+      const content = editor.getValue()
+      const headingPattern = new RegExp(
+        `^#{1,6}\\s+${escapeRegex(heading.text)}\\s*$`,
+        'm'
+      )
+      const match = headingPattern.exec(content)
+      if (!match) return
 
-      view.state.doc.descendants((node, pos) => {
-        if (foundPos !== null) return false
-        if (node.type.name === 'heading' && node.attrs.level === heading.level) {
-          if (node.textContent.trim() === heading.text) {
-            if (currentIndex === index) {
-              foundPos = pos
-              return false
-            }
-            currentIndex++
-          }
-        }
-        return true
-      })
+      const pos = match.index
 
-      if (foundPos === null) return
+      // 通过 DOM 操作滚动 textarea 到对应位置
+      const container = document.querySelector('.metona-editor-wrapper') as HTMLElement | null
+      if (!container) return
 
-      const tr = view.state.tr
-        .setSelection(TextSelection.create(view.state.doc, foundPos, foundPos))
-        .scrollIntoView()
-      view.dispatch(tr)
-      view.focus()
+      const textarea = container.querySelector('textarea')
+      if (!textarea) return
+
+      // 估算滚动位置（简单方法：按行数比例）
+      const linesBefore = content.substring(0, pos).split('\n').length
+      const lineHeight = 24 // 估算行高
+      textarea.scrollTop = linesBefore * lineHeight
+
+      // 设置光标位置
+      textarea.focus()
+      textarea.setSelectionRange(pos, pos)
     } catch {
-      // Position may be invalid if content has changed
+      // 导航失败，静默忽略
     }
   }, [])