### What problem does this PR solve?
This PR implements comprehensive Arabic language support for the RAGFlow
application. The changes include:
- Complete Arabic translation of all UI text elements in the web
interface
- RTL (right-to-left) layout support for Arabic content
- Localization updates for all supported languages (ar, bg, de, en, es,
fr, id, it, ja, pt-br, ru, vi, zh-traditional, zh)
- UI component adjustments to properly display Arabic text and support
RTL layout
The implementation ensures that Arabic-speaking users can fully interact
with the application in their native language with proper text rendering
and layout direction.
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
<img width="2866" height="1617" alt="image"
src="https://github.com/user-attachments/assets/f2751b34-1b65-4867-b81d-a1068c17b9b7"
/>
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Co-authored-by: Yingfeng <yingfeng.zhang@gmail.com>
### What problem does this PR solve?
Update **Chat** UI:
- Align to the design.
- Update `<AudioButton>` visualizer logic.
- Fix keyboard navigation issue.
### Type of change
- [x] Refactoring
## Summary
- keep assistant message containers stretched to available width
- avoid width collapse during streaming by allowing flex items to shrink
## Test plan
- not run (not requested)
Fixes#12985
Made with [Cursor](https://cursor.com)
Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: Liu An <asiro@qq.com>
### What problem does this PR solve?
Refactor: UmiJs -> Vite+React
### Type of change
- [x] Refactoring
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Co-authored-by: Liu An <asiro@qq.com>