Root cause: the new conditions system's 'signal' special form shadowed
the reactive 'signal' function. (signal 0) in island bodies raised
'Unhandled condition: 0' instead of creating a signal dict.
Fix: rename condition special form to 'signal-condition' in the CEK
dispatcher. The reactive 'signal' function now works normally.
adapter-html.sx: remove cek-try that swallowed island render errors.
Islands now render directly — errors propagate for debugging.
sx_render.ml: add sx_render_to_html that calls SX adapter via CEK.
Results: 4/5 island SSR tests pass:
- Header island: logo, tagline, styled elements ✓
- Navigation buttons ✓
- Geography content ✓
- Stepper: partially renders (code view OK, ~cssx/tw in heading)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>