Codex Desktop: allow hiding or collapsing the composer while reading

Feature request

Please add a way to temporarily hide, collapse, or move the message composer/input box in Codex Desktop.

Problem

When reading long responses, files, diffs, or review output, the composer at the bottom of the window can crowd or obscure the text area. This makes the app feel harder to use as a reading and review surface, especially during longer Codex sessions.

Suggested UX

• Add a small collapse/expand control for the composer.
• Add a keyboard shortcut, for example Cmd+Shift+H, to hide/show the composer.
• When hidden, show a small floating button or affordance to restore typing.
• Optionally auto-hide the composer while scrolling/reading, then restore it when the user focuses the input area or starts typing.

Why this matters

Codex Desktop is often used for reading generated explanations, code reviews, logs, plans, and file content, not only for typing prompts. A reader mode or collapsible composer would make long-session review much more comfortable without changing the core interaction model.