### What problem does this PR solve?
Feat: Make the agent dialog window exposed to the outside world fill in
the begin form #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: Downstream operators can get the variables defined by the user
input operator #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Feat: Upload files in the chat box on the agent page #3221
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
