[Bug] TUI fullscreen mode: input field pushed off-screen when task list present

Question

**Bug Description**
In TUI fullscreen mode, if there's a task list, it pushes the input field down beyond the screen, and the cursor can't fit there. It's completely impossible to type if the output + task list takes up more than about 2/3 of the screen, and the input field doesn't fit in the remaining 1/3.

**Environment Info**
- Platform: darwin
- Terminal: vscode
- Version: 2.1.146
- Feedback ID: c15d8074-5104-4c45-92d7-df54b5ea491a

**Errors**
```json
[]
```