lith/Caddyfile: let Kubo's CORS header pass through unchanged
The header_down -Access-Control-Allow-Origin strip fired but the followup
set didn't re-add the header, leaving ipfs.aesthetic.computer with no CORS
header at all. Kubo already emits a single * so the simplest fix is to
remove both header_down directives and pass upstream through verbatim.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>