xterm.js 6.0.0 natively handles DEC mode 2026 (synchronized output),
which renders Ink's cursor-up redraws atomically at the parser level.
This eliminates split-frame rendering that caused table header loss
and garbled overlapping text in Claude CLI sessions.
- Migrate from xterm/xterm-addon-* to @xterm/* scoped packages
- Update build.mjs and postinstall.js vendor paths
- Remove old xterm 5.x dependencies