- Playground `localValidator` should use @rjsf/validator-ajv8
- Upgrade Vite and @vitejs/plugin-react to latest
- Alias `ajv` to `ajv8` because in the playground, Vite erroneously imports Ajv 6
- Report any schema error thrown by Ajv
- Disable Ajv's strict mode by default
- Add RJSF-specific additional properties keywords to Ajv to prevent errors from being reported in strict mode.