chore: prepare 0.1.0-beta.0 and rewrite the README

[ahmdshrif]

Beta preparation

• Version 0.1.0-beta.0, published under the beta dist-tag so it never becomes latest by accident.
• CHANGELOG.md with the feature list and the known limitations.
• RELEASING.md with the publish checklist.
• Verified a clean install of the packed tarball into a fresh Expo SDK 55 app: peers install, types check, and the iOS bundle builds.
• Found and documented an install-order trap: installing the library before the peers makes npm resolve Reanimated 4.7, which requires React Native 0.86+ and conflicts with SDK 55. The README now tells Expo users to install peers with expo install first.

README rewrite

Modelled on what the best React Native libraries do (FlashList, mmkv, bottom-sheet, VisionCamera, gesture-handler):

• Demo GIF at the top (520 KB) showing sideways scrolling with pinned columns, sorting, selection, dark mode and server paging. The library had no visuals at all before.
• Link bar, four badges, and a "why this grid" section that leads with the pinned-column sync argument.
• One quick-start example instead of tables above the fold; a separate column-patterns section.
• Compatibility table, comparison table (including the competing package and what it does better), and an explicit limitations list.
• Long prop tables moved out of the README into docs/api.md, docs/server-data.md and docs/theming.md. README is now 207 lines instead of 243, with far more in it.

Testing

37 unit tests, lint and typecheck pass. No library source changes in this PR apart from the version bump.