mentionedUserIds and mentionedCommunities [{id, name, managerIds}] list who a comment mentions — picked or typed as @nickname, validated by CMS, without the real author, each target once. A mentioned community carries its managers and its name, so a consumer needs no community data. HasMentions reports whether a comment mentions anyone. Both fields are optional: older producers and consumers are unaffected.
Co-Authored-By: Claude Opus 5.5 (1M context) noreply@anthropic.com
Closes FL-1525