Restore Circuit UI test suite

[txbrown]

Summary

• restores root workspace scripts after the package rename to @circuit-ui/core
• adds missing Jest/worklets mocks and DOM typings needed by the current RN component tests
• refreshes snapshots after the current rendered output/mocks changed
• refreshes yarn.lock and adds the react-native-worklets dev dependency for the UI package tests

Validation

• yarn typecheck
• yarn test:unit (passes; existing piano-roll no-sample warnings still print in ClipEditor tests)