Add Schema module with functions for creating and migrating versioned
values. This provides the runtime foundation for schema evolution.
Schema module functions:
- Schema.versioned(typeName, version, value) - create versioned value
- Schema.migrate(value, targetVersion) - migrate to new version
- Schema.getVersion(value) - get version number
Changes:
- Add Versioned, Migrate, GetVersion builtins to interpreter
- Add Schema module to global environment
- Add Schema module type to type environment
- Add 4 tests for schema operations
- Add examples/versioning.lux demonstrating usage
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>