TUI re-renders full conversation history to terminal scrollback on each response, causing exponential scrollback growth

Version: Claude Code v2.1.113

Platform: Windows 10 Pro, Windows Terminal

Description:

On each new response, Claude Code appears to re-render the entire conversation to the terminal output buffer rather than appending only the new response. This causes the terminal scrollback to accumulate duplicate copies of the full conversation — one copy per exchange — each preceded by the startup splash screen.

Steps to reproduce:

1. Start Claude Code in Windows Terminal
2. Have a conversation with several exchanges
3. Scroll up in the terminal scrollback past the beginning of the current visible session
4. Observe a second copy of the conversation above the splash screen; scroll further to find more copies

Expected behavior: Scrolling past the start of the session reaches empty scrollback (or the previous terminal session). Each exchange appends only new content.

Actual behavior: The scrollback contains N full copies of the conversation for a session with N exchanges. Scrollback length grows quadratically, making it very difficult to navigate to a specific point in a long conversation by dragging the scrollbar.

Impact: In long conversations, the scrollback becomes many times longer than the actual conversation, making backward navigation impractical.