Function countBlufEvidenceAnchors

Count evidence anchors inside a BLUF prose paragraph. Anchors are the traceable tokens that lift a claim from rhetoric to verifiable intelligence:

• dok_id-shaped codes (HD12345, FiU17)
• parliamentary doc references (Prop. 2025/26:247, Skr. 2025/26:259)
• vote IDs (votering_id=…, Votering(\s+\d|:\s+\w))
• primary-source URLs on data.riksdagen.se / riksdagen.se / regeringen.se / scb.se / imf.org
• markdown anchors to per-document sections (#rm-)