KeyEncoder mapped TAB to a plain tab regardless of Shift, so Shift+Tab sent the
same byte as Tab. Apps that use backtab for reverse navigation (fish completion
menu, helix theme picker) never saw it. Emit CSI Z when Shift is held.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 93d53fcef6)
paintIncremental's per-row dirty work was negated by present() calling
PixelBuffer.updateBuffer(null), which re-uploads the whole pane texture
every frame. Track the vertical band of buffer rows written since the
last present and hand that to updateBuffer so only changed rows upload.
The border is now drawn without extending the dirty band (its pixels are
unchanged between incremental frames). Also clamp blitGlyph's rectangle
once instead of bounds-checking every glyph pixel in the inner loop.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
gregor
