Add three commerce intelligence patterns for creator monetization

Patterns added:
- extract_affiliate_products: extracts sponsored + organic affiliate opportunities from any transcript
- extract_video_commerce_entities: identifies all commercial entities in video content by category, timestamp position, and purchase likelihood
- analyze_monetization_opportunities: maps audience intent to revenue opportunities (affiliate, sponsorship, digital products)

These fill a gap in the existing extract_sponsors pattern — sponsors are just one slice; organic product mentions often convert better and these patterns surface both.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>