Method updateTheme

src/core/nodeviews/code-block.ts:1354–1358

* 更新主题

(isDark: boolean)

   * 更新主题
   */
  private updateTheme(isDark: boolean): void {
    this.cm.dispatch({
      effects: this.themeCompartment.reconfigure(createThemeExtension(isDark)),
    });
  }

  /**
   * 更新搜索高亮（将 ProseMirror 搜索状态映射到 CodeMirror 装饰）