perf: cheaper shell refreshes, one copy of Codex streaming text, no MCP wait polling (#15033)

Co-authored-by: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
c138163c8cTheo Browne committed on 10/5/2026, 10:39:24 PM· committed by GitHubparent2afe87e
21 files changedLine totals unavailable