### What problem does this PR solve?
Fix: Fixed an issue where adding session variables multiple times would
overwrite them.
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Fixes: Added session variable types and modified configuration
- Added more types of session variables
- Modified the embedding model switching logic in the knowledge base
configuration
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Feat: Place the new mcp button at the end of the line. #10427
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Fixes: Bugs fixed
- Removed invalid code,
- Modified the user center style,
- Added an automatic data source parsing switch.
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Feat: Globally defined conversation variables can be selected in the
operator's query variables. #10427
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feature: Added global variable functionality
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
