[BUG] New bottom UI overlaps with custom statusLine on macOS (Ghostty/libghostty)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

After the recent UI update, the new bottom bar elements (below the input prompt) visually overlap with my custom statusLine configuration. The statusline renders correctly on its own, but the new Anthropic UI draws on top of it, making both unreadable.

The custom statusLine shows project info (branch, timers, cost) and the new UI elements fight for the same terminal rows.

What Should Happen?

Claude Code should account for custom statusLine content when rendering the new bottom UI, or provide an option to disable the new bottom bar elements to avoid overlap.

Error Messages/Logs

No errors — purely visual rendering issue.

Steps to Reproduce

1. Configure a custom statusLine in settings.json (e.g. using claude-statusline or a custom script)
2. Launch Claude Code in a terminal with the statusLine visible below the prompt
3. Observe the new bottom UI elements overlapping with the statusLine

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Worked fine before the new bottom bar UI was introduced.

Claude Code Version

Latest (as of 2026-04-02)

Platform

Max subscription

Operating System

macOS (Darwin 25.3.0)

Terminal/Shell

libghostty (via cmux), Ghostty backup

Additional Context

Related: #21867 (request to hide built-in status elements), #21647 (prompt bar UI compaction).

Screenshot will be added in a follow-up comment.