Release v20.43.7

Summary

Fixes two command correctness issues in Arc React forms and dialogs:

• Empty string values were rejected by core required-property validation even when no explicit empty-string validator existed, making client validation stricter than server/domain validation.
• Reactive currentValues / useCommand syncing ignored explicit null and undefined values, so cleared external state could leave stale command values for validation and submit.

Fixed

• Fixed command required-property validation to treat only null and undefined as missing, letting explicit validators decide whether empty strings are invalid. (#2307)
• Fixed currentValues and useCommand value syncing so explicit null and undefined values clear command properties instead of leaving stale values. (#2307)

Changed

• Clarified CommandForm validation docs to distinguish required field metadata from explicit empty-string validation rules. (#2307)