ci(facts): use the existing org-level REGISTRY_TOKEN

checkFacts needs to read link, servuo-plugins, website and installer, and
the automatic per-run token is scoped to this repo alone. Rather than mint
a new secret, the workflow uses REGISTRY_TOKEN, which already exists at the
org level with the right permissions.

The secret is named for the registry and the script reads GITEA_TOKEN; the
mapping stays in the workflow so the script keeps asking for what it
actually wants -- a Gitea token -- rather than this org's secret name.

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

scripts/checkFacts.mjs

@@ -231,8 +231,9 @@ async function main() {
       'checkFacts: GITEA_TOKEN is not set.\n\n' +
         '  Anonymous raw fetches fail on this Gitea instance, and a fact check that skips\n' +
         '  itself is worse than no fact check — a stale version would ship silently.\n\n' +
-        '  Locally:  GITEA_TOKEN=$(grep -o "[^=]*$" ~/.gitea_token_claude) npm run check:facts\n' +
-        '  In CI:    set GITEA_TOKEN from the repository secret.\n'
+        '  Locally:  GITEA_TOKEN=<a token that can read the org> npm run check:facts\n' +
+        '  In CI:    already wired — .gitea/workflows/pr-checks.yml maps the org-level\n' +
+        '            REGISTRY_TOKEN secret into GITEA_TOKEN for this step.\n'
     );
     process.exit(2);
   }