Add pretty-print, read-file, env-list-typed primitives to OCaml kernel.
Convert Python reference data (attrs, headers, events, primitives) to SX
data files. Implement page helpers (component-source, handler-source,
read-spec-file, reference-data, etc.) as pure SX functions.
The helper dispatcher in HTTP mode looks up named functions in the env
and calls them directly, replacing the Python IO bridge path.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>