v0.3.10: 全面优化增强 — 17项Bug修复/稳定性/功能改进

P0 致命Bug修复:
- A1: openFolderDialog 类型/运行时崩溃(文件夹打开功能完全失效)
- A2: SourceEditor 受控textarea手动改DOM反模式
- A3: tabStore.updateTabContent 内容相同时误标isModified

死代码清理:
- B1: 删除menu:*/save/as/viewMode 三个永不触发的IPC通道

健壮性修复:
- E1: rehypeFixImages 路径规范化+防越界加固
- E2: getFileName 尾斜杠返回正确文件名
- E3: EditorToolbar 行内代码按钮改用toggleInlineCodeCommand
- E4: ErrorBoundary 内联样式抽为CSS类

功能增强:
- D1: 标签页拖拽排序(tabStore.moveTab + TabBar DnD + CSS)
- D2: Milkdown自动配对括号/引号(ProseMirror插件)
- D3: 状态栏自动保存开关可点击
- D4: 文档大纲活跃标题高亮(useActiveHeading hook)
- D5: 关闭窗口前flush防抖数据(flushSaveToDB)
- D6: 搜索替换支持正则表达式

类型/架构:
- C2: preload类型集中定义(ElectronAPI契约)
- __pycache__ typo修复

文档/版本:
- README/DESIGN同步为Milkdown + v0.3.10
- 项目结构树/技术栈/快捷键表更新

验证: typecheck(仅7预存), lint✅, test 96/96, vite build✅

src/renderer/components/ErrorBoundary/ErrorBoundary.tsx

@@ -35,52 +35,20 @@ export class ErrorBoundary extends Component<Props, State> {
         return this.props.fallback
       }
 
-      const isDev = (typeof import.meta !== 'undefined' && (import.meta as { env?: { DEV?: boolean } }).env?.DEV) ?? false
+      const isDev =
+        (typeof import.meta !== 'undefined' &&
+          (import.meta as { env?: { DEV?: boolean } }).env?.DEV) ??
+        false
 
       return (
-        <div
-          style={{
-            display: 'flex',
-            flexDirection: 'column',
-            alignItems: 'center',
-            justifyContent: 'center',
-            height: '100vh',
-            padding: '2rem',
-            textAlign: 'center',
-            fontFamily: 'system-ui, -apple-system, sans-serif',
-          }}
-        >
-          <h2 style={{ marginBottom: '1rem', color: '#e74c3c' }}>
-            应用遇到了错误
-          </h2>
+        <div className="error-boundary-root" role="alert">
+          <h2 className="error-boundary-title">应用遇到了错误</h2>
           {isDev && (
-            <pre
-              style={{
-                padding: '1rem',
-                backgroundColor: '#f8f9fa',
-                borderRadius: '8px',
-                maxWidth: '600px',
-                overflow: 'auto',
-                fontSize: '0.875rem',
-                color: '#666',
-              }}
-            >
+            <pre className="error-boundary-detail">
               {this.state.error?.message}
             </pre>
           )}
-          <button
-            onClick={this.handleReset}
-            style={{
-              marginTop: '1rem',
-              padding: '0.5rem 1.5rem',
-              border: 'none',
-              borderRadius: '6px',
-              backgroundColor: '#3498db',
-              color: 'white',
-              cursor: 'pointer',
-              fontSize: '1rem',
-            }}
-          >
+          <button className="error-boundary-reset" onClick={this.handleReset}>
             重试
           </button>
         </div>