v0.3.4: Bug修复+性能优化+文档大纲功能

🔴 Bug修复 (6):
- Sidebar反斜杠正则修复 (Windows路径规范化)
- FileWatcher文件删除后自动恢复监听
- SearchReplace replaceAll防过期匹配位置
- openFolderDialog null结果守卫
- 保存异常时空路径保护
- Markdown绝对路径图片拼接修复

🟡 性能优化:
- Editor切换标签时内容比较，相同跳过replaceAll

🔵 代码质量:
- 创建共享常量模块 src/shared/constants.ts，消除双副本

🎯 新增功能:
- 文档大纲 (Table of Contents) — 侧边栏标题导航

🔧 换行符统一: CRLF → LF

src/renderer/components/ErrorBoundary/ErrorBoundary.tsx

@@ -1,88 +1,88 @@
-import { Component, ErrorInfo, ReactNode } from 'react'
-
-interface Props {
-  children: ReactNode
-  fallback?: ReactNode
-}
-
-interface State {
-  hasError: boolean
-  error: Error | null
-}
-
-export class ErrorBoundary extends Component<Props, State> {
-  constructor(props: Props) {
-    super(props)
-    this.state = { hasError: false, error: null }
-  }
-
-  static getDerivedStateFromError(error: Error): State {
-    return { hasError: true, error }
-  }
-
-  componentDidCatch(error: Error, errorInfo: ErrorInfo): void {
-    // eslint-disable-next-line no-console -- React error boundary standard pattern
-    console.error('ErrorBoundary caught an error:', error, errorInfo)
-  }
-
-  handleReset = (): void => {
-    this.setState({ hasError: false, error: null })
-  }
-
-  render(): ReactNode {
-    if (this.state.hasError) {
-      if (this.props.fallback) {
-        return this.props.fallback
-      }
-
-      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>
-          <pre
-            style={{
-              padding: '1rem',
-              backgroundColor: '#f8f9fa',
-              borderRadius: '8px',
-              maxWidth: '600px',
-              overflow: 'auto',
-              fontSize: '0.875rem',
-              color: '#666',
-            }}
-          >
-            {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',
-            }}
-          >
-            重试
-          </button>
-        </div>
-      )
-    }
-
-    return this.props.children
-  }
-}
+import { Component, ErrorInfo, ReactNode } from 'react'
+
+interface Props {
+  children: ReactNode
+  fallback?: ReactNode
+}
+
+interface State {
+  hasError: boolean
+  error: Error | null
+}
+
+export class ErrorBoundary extends Component<Props, State> {
+  constructor(props: Props) {
+    super(props)
+    this.state = { hasError: false, error: null }
+  }
+
+  static getDerivedStateFromError(error: Error): State {
+    return { hasError: true, error }
+  }
+
+  componentDidCatch(error: Error, errorInfo: ErrorInfo): void {
+    // eslint-disable-next-line no-console -- React error boundary standard pattern
+    console.error('ErrorBoundary caught an error:', error, errorInfo)
+  }
+
+  handleReset = (): void => {
+    this.setState({ hasError: false, error: null })
+  }
+
+  render(): ReactNode {
+    if (this.state.hasError) {
+      if (this.props.fallback) {
+        return this.props.fallback
+      }
+
+      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>
+          <pre
+            style={{
+              padding: '1rem',
+              backgroundColor: '#f8f9fa',
+              borderRadius: '8px',
+              maxWidth: '600px',
+              overflow: 'auto',
+              fontSize: '0.875rem',
+              color: '#666',
+            }}
+          >
+            {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',
+            }}
+          >
+            重试
+          </button>
+        </div>
+      )
+    }
+
+    return this.props.children
+  }
+}