Upgrade React to 19.2.3 and fix useRef type errors

- Upgrade react and react-dom from 18.3.1 to 19.2.3
- Upgrade @types/react and @types/react-dom to 19.2.3 (matching versions)
- Fix useRef hooks to include explicit initial values (React 19 requirement)
- Update ref prop types to handle React 19's stricter null handling
- Fix eslint config for reactHooks.configs compatibility

Co-authored-by: d10c <9970661+d10c@users.noreply.github.com>

Author: Copilot