v0.4.1

Added

• Directory-based explanation storage: Explanation sessions now store files organized by directory structure, matching the topic hierarchy in state.json for better session management and navigation.

新增

• 基于目录的解释存储：解释会话现在会按目录结构存储文件，与 state.json 中的主题层级结构相匹配，从而更好地管理和导航会话。