### What problem does this PR solve?
RAGFlow had no Turkish language support. This PR adds Turkish (tr)
locale translations to the UI.
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Co-authored-by: Mustafa YILDIZ <mustafa.yildiz@cilek.com>
### 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"
/>
---------
Co-authored-by: Yingfeng <yingfeng.zhang@gmail.com>
### What problem does this PR solve?
Fix: UI Placeholder and Hint Optimization
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
fix: Optimize internationalization configuration
- Update multi-language options, adding general translations for
functions like Select All and Clear
- Add internationalization support for modules like Chat, Search, and
Datasets
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Feat: Modify the background color of the agent canvas #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: Add the option to use the knowledge graph to the retrieval form
#3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
