[Feat] 历史会话列表增加收藏/置顶按钮

[bmwa0813]

1、当前对话页面增加清空对话按钮。这是使用频率远大于“编辑”按钮的必备功能。当前由于没有此功能，用户只能新开会话。虽然效果相同，但会导致对话列表轻松累计上百条本无需保留的无价值历史会话。

2、历史会话列表需要收藏/置顶功能。当前仅有一键清除所有对话，无法高效的筛选与保留有价值的历史会话。

上述两个功能的同时缺失，起到了互相放大的效果，令当前使用体验差强人意。
建议优先优化此功能💕

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically.

---

Title: Add a clear dialogue button to the conversation page; add a favorite/pin button to the historical conversation list

1. A clear conversation button is added to the current conversation page. This is an essential feature that is used much more frequently than the Edit button. Currently, since this function does not exist, users can only open new sessions. Although the effect is the same, it will cause the conversation list to easily accumulate hundreds of worthless historical conversations that do not need to be retained.

2. The historical conversation list needs the collection/top function. Currently, there is only one click to clear all conversations, and it is impossible to efficiently filter and retain valuable historical conversations.

The simultaneous lack of the above two functions has the effect of amplifying each other, making the current user experience unsatisfactory.
It is recommended to prioritize optimizing this function💕

[zmh-program]

duplicate #144

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically.

---

duplicate #144

[Xuanyu0610]

增加将某个对话所有内容保存为文档的功能

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically.

---

Added the ability to save the entire content of a conversation as a document

[zmh-program]

增加将某个对话所有内容保存为文档的功能

not consider

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically.

---

Added the ability to save all content of a conversation as a document

not consider