Remove compile_js RPC method
The compile_js method for ahead-of-time JS compilation is out of scope
for this interactive toplevel tool. Remove it from:
- API definition (toplevel_api.ml, toplevel_api_gen.ml)
- Implementation (impl.ml)
- Worker registrations (worker.ml, unix_worker.ml)
- Client libraries (js_top_worker_client.ml/mli, js_top_worker_client_fut.ml)
- Tests (node_test.ml, unix_test.ml)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>