Server computes SHA-256 hash of all component source at startup.
Client signals its cached hash via cookie (sx-comp-hash). On full
page load: cookie match → server sends empty script tag with just
the hash; mismatch → sends full source. Client loads from
localStorage on hit, parses inline + caches on miss.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>