Add render-to-sx eval wrapper, preload handler mocks, load forms.sx
- render-to-sx: OCaml wrapper that parses source strings then evaluates
via aser — unblocks test-aser.sx tests that pass string arguments
- Pre-load test-handlers.sx before test scan so reset-mocks!/helper are
available to test-examples.sx (fixes 24 reset-mocks! failures)
- forms.sx loaded — provides defpage, stream-chunk-id, normalize-binding-key
- context registered as Sx_primitives primitive (not just env binding)
- cek-call, cek-run, now-ms, regex-find-all stubs added
1578 → 1661 passing tests (+83).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>