### What problem does this PR solve?
Feat: Replace color variables according to design draft #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Fix: Fixed the issue that the condition of deleting the classification
operator cannot be connected anymore #3221
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Feat: Adjust the style of the agent canvas connection line #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: The delete button is displayed only when the cursor is hovered
over the connection line #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: Constructing query parameter options for the Retrieval operator
#3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: Enables the message operator form to reference the data defined by
the begin operator #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: Render agent details #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
