DR-081a — A19 confidence reserved-value policy: producer emits `strong|partial` only (DR-079 addendum)

Retired/tombstoned S504. Re-homed (S504 register sweep): a deterministic producer computation rule, pinned in producer code + tests; consumer already cites it. Substance home: canonical:scripts/cocoindex_pipeline/producer/enrich.py + scripts/tests/test_producer_frontmatter.py (consumer: lib/okf/bundle-graph.ts). Original ADR text retained below; this id stays on disk so citations resolve and the number is never re-issued. no-content/needs-SME are carried + validated in the concept-frontmatter contract but are NEVER producer-auto-set — reserved for system-baseline/stub scaffolding and the human/SME-review lane respectively. Confidence is a DETERMINISTIC producer computation, never model-authored: strong if the resource is a per-row anchor (source_documents | reference_items) AND ≥2 distinct record-anchor citations (named module constant), else partial.