Module Aggregator/Metadata/ArtifactHighlight

Description

Thin re-export barrel that aggregates the three split highlight modules back into the single public surface expected by article-metadata.ts:

• extractArtifactHighlight — primary editorial-artefact walker (see editorial-highlight.ts)
• extractPriorityFindingHighlight — fallback priority-finding extractor (see priority-finding-highlight.ts)
• isTranslatedSiblingBrief — translated-sibling filter predicate (see translated-sibling.ts)