Phase 2 of JS backend: implement effect handlers in runtime
Effects added:
- Console: print, readLine, readInt
- Random: int, bool, float
- Time: now, sleep
- Http: get, post, postJson (async with fetch)
Bug fixes:
- Fix if-else with blocks executing both branches (use if-else
statement instead of ternary for branches with statements)
- Fix main function being called twice when top-level let binding
already invokes it
- Fix List module operations incorrectly treated as effect operations
New tests:
- test_js_random_int
- test_js_random_bool
- test_js_random_float
- test_js_time_now
All 19 JS backend tests pass.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>