CellState adds cell-level diffing, native scrollback

The interesting part here is not “React in the terminal”; it’s the choice to treat the viewport like a raster surface and leave scrollback alone. That makes CellState feel like a practical answer to flicker in agent terminals, not just another TUI abstraction.

• –Cell-by-cell diffing should cut redraw work dramatically for streaming output, progress updates, and chatty agent logs.
• –Preserving native scrollback, text selection, and Cmd+F is a real UX win over alternate-screen TUIs, especially for developer tools people keep open all day.
• –The tradeoff is explicit: once content lives in immutable scrollback, you can reduce flicker but not eliminate every edge case when the buffer changes shape.
• –The README’s benchmark table and property-based xterm.js tests suggest the project is trying to be production-grade, not a novelty demo.
• –For teams already building React-based CLI tooling, it lowers the barrier to a polished terminal UI; for everyone else, a lower-level stack may still be simpler.