Adds a compile-only JavaScript/TypeScript authoring path that extracts a JSON-compatible workflow({...}) object, lowers it to the existing WorkflowSpec IR, and runs the Rust validation gate before execution.
Includes a branch/reduce .workflow.js example and a short authoring design note comparing YAML/JSON, Starlark, JavaScript, and TypeScript. The compiler rejects effectful JavaScript constructs instead of executing workflow source as a second runtime.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>