Lambda multi-body fix: sf-lambda used (nth args 1), dropping all but the first
body expression. Fixed to collect all body expressions and wrap in (begin ...).
This was foundational — every multi-expression lambda in every island silently
dropped expressions after the first.
Reactive islands: fix dom-parent marker timing (first effect run before marker
is in DOM), fix :key eager evaluation, fix error boundary scope isolation,
fix resource/suspense reactive cond tracking, fix inc not available as JS var.
New essay: "React is Hypermedia" — argues that reactive islands are hypermedia
controls whose behavior is specified in SX, not a departure from hypermedia.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>