mod/related-ids and mod/reporters-of find reports about a subject via a Prolog
relational query (report(Id, _, 'subject')) — the policy substrate reused for
retrieval. mod/dedup-reports collapses identical reports by a normalized
reporter|subject|reason key; mod/distinct-reporters-of counts unique reporters.
Own suite (tests/link.sx). +12 tests.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>