Add react-datatable; remove stale gigatables entry

[FroeMic]

Adds react-datatable under Table with documentation as the primary link and a demo link. No other list entries are changed.

[FroeMic]

Hi @brillout — hope a direct PR is ok.

I kept getting stuck between opaque grid widgets and headless TanStack setups where I still had to wire filters, views, virtualization, and server pagination myself. react-datatable is basically the middle path: TanStack Table + shadcn-style Radix bits + Tailwind, but shipped as one copy-in kit with real product UX. Happy to tweak wording or the removal pick if you’d rather drop a different stale line.

— Michael

[FroeMic]

Quick correction: the product is not open source, so the listing now points at documentation only—no GitHub repo link. Thanks for bearing with the noise.