React 19 support in the React wrapper

[lesnik512]

What to build

@quotidianlabs/emojis-react installs alongside React 19 without a peer dependency
conflict, and the picker renders in a React 19 application.

This is the release that answers Upstream issue missive#967. It ships immediately after the
rename, as its own release, so the rename lands as a release that changed nothing
else.

Acceptance criteria

• The React wrapper's react peer range accepts React 19 alongside the versions it already accepts
• Only the React wrapper is versioned and republished; core and Data are untouched
• The release gate passes with React 19 installed in the scratch application
• Installing the wrapper with React 19 produces no peer warning and needs no overrides block

Notes

The wrapper imports only React, useEffect and useRef and calls createElement.
It uses none of the APIs React 19 removed, and core renders through Preact and does
not import React at all. Upstream PR missive#1008 is the same single-line change, open and
unmerged, which corroborates that this is a metadata fix rather than a code change.

Blocked by

• The rename spec