Summary:
- Add a mouse-only jump-to-latest affordance when the transcript is scrolled away from the live tail.
- Hide the control at the tail or when mouse capture is disabled.
- Add tests for visibility and click behavior.
Maintainer verification on current origin/main:
- cargo test -p deepseek-tui jump_to_latest --locked
- cargo fmt --all -- --check
- git diff --check origin/main...HEAD
Closes#971
Turisla
dd822edcfc