It existed for the incremental re-render: a shorter render left the previous
one's view lines in the tail (deliberately, to avoid a blank frame), and this
cleared them once the new content was fully read. Async renders now build
off-screen and swap in whole, so refreshViewLinesIfNeeded truncates the view
lines to the buffer and no tail can form. All the call at end-of-input still
did was discard every wrapped line and force the whole buffer to be re-wrapped
on the next draw, which is pure work on a large diff.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>