[Feature Request]AutoClose XML tag

## Describe the solution you'd like
Automatic tag closing when XML tags are inputed in the chat input field.

## Why the solution needed
Claude can improve accuracy by using XML tags.
Automatic XML closure improves UX.
https://docs.anthropic.com/claude/docs/use-xml-tags

## Additional context

## Implementation feasibility

Are you willing to discuss the solution with us, decide on the approach, and assist with the implementation?

- [ ] Yes
- [ ] No

No files or tests are named. Start by locating the chat input field and its input-handling entry point, then confirm how XML tags should be recognized and closed; done should mean the chat input automatically closes XML tags and the resulting interaction improves the stated UX.

Written by the indexing model from the issue text.