TUI input box does not stick to the bottom of the terminal, making it hard to type after scrolling through history

What feature would you like to see?

Description

In the interactive TUI of Kimi Code CLI, when a conversation produces a long
output and the user scrolls up to review previous messages, the input box at
the bottom scrolls out of view along with the content. The user then has to
scroll all the way back down to the bottom before they can continue typing,
which breaks the flow of reviewing context and entering follow-up commands.

Steps to reproduce

1. Launch kimi to enter an interactive session.
2. Run a task that produces a long output (for example, ask Kimi to read
   multiple files, run tests, and print results).
3. After the output finishes, scroll up in the terminal to review earlier
   content.
4. Try to type a new command — the input box is no longer visible.

Expected behavior

The input box should remain docked at the bottom of the terminal window,
while the message history area scrolls independently. Even when the user
scrolls up to review past output, the input box should always be visible and
ready for typing.

Reference UX: browser-based chat UIs, Aichat, ShellGPT, and similar tools
usually keep the input box sticky/fixed.

Actual behavior

When scrolling up through historical output, the input box moves upward with
the content and disappears from view.

Environment

• Kimi Code CLI version: 0.17.1
• OS: Linux / macOS / Windows (all affected)
• Terminal: any terminal emulator

Suggested solutions

1. Make the input box sticky/fixed at the bottom of the TUI layout.
2. Allow the message history area to scroll independently from the input
   box.
3. Alternatively, add a tui.toml option such as sticky_input = true so users
   can opt in.

Why this matters

When using Kimi Code CLI for complex tasks, users often need to review
earlier output (error logs, code diffs, analysis) while continuing to ask
follow-up questions or issue new commands. A non-sticky input box interrupts
this read-then-type loop and hurts productivity.

Thanks for considering this improvement!

Additional information

No response

Start at the interactive TUI entry point reached by launching kimi and reproduce the issue with a long-output task, then scroll through the history. Trace how the message history and input box share the terminal layout; done means the history scrolls independently while the input box remains visible and ready for typing.