### What problem does this PR solve?
Optimized the chat interface (including the chat API after sharing)
1. Change the background color of the dialog box between the assistant
and the user (use the theme color of the interface)
2. Add rounded corners to the dialog box
3. When the input box is empty, you can't click the send button(because
some models will report an error when sending empty data)
Color reference(can be a bit subjective)：
### Type of change
- [x] Refactor
Co-authored-by: 海贼宅 <stu_xyx@163.com>
### What problem does this PR solve?
fix: thumbnails are too large in the chat box #818
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
feat: Support for conversational streaming
#709
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Embed the chat window into other websites through iframe
#345
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
some chunk method pictures are not in English #437
feat: set the height of both html and body to 100%
feat: add SharedChat
feat: add shared hooks
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
