chore(catalog): keep only Voyage in the open catalog

Operator decision 2026-10-06: until further notice only Voyage stays in
the open/ organisation; repositories and plugins are added back when
they are good enough. The eight other plugins move to the operator's
private marketplace. Manifest, README and PUBLIC_REPOS changed in the
same commit, as the public-link gate requires.

check-public-links: 0 hits; check-versions, check-retired-refs,
check-nav-golden, check-okf-parity exit 0; 233 of 233 tests pass.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/check-public-links.mjs

@@ -18,15 +18,7 @@ const HERE = dirname(fileURLToPath(import.meta.url));
 
 // Org repositories the catalog may link to — the published plugins plus this catalog.
 export const PUBLIC_REPOS = [
-  'ai-psychosis',
-  'graceful-handoff',
-  'human-friendly-style',
   'ktg-plugin-marketplace',
-  'linkedin-studio',
-  'ms-ai-architect',
-  'okr',
-  'repo-mailbox',
-  'repo-standard',
   'voyage',
 ];