Two changes:
1. rerankReleaseGroups now uses blended scoring (text relevance +
popularity) like artists, instead of pure popularity. This
prevents obscure albums with high listen counts from outranking
direct MB search matches.
2. boostNameMatches now uses rgMatchTier() for release groups, which
checks artist credit before title. Albums BY the searched artist
(tier 0: exact credit match) rank above albums that merely
mention the artist in the title (tier 3: title substring).
For 'hop along': Painted Shut by Hop Along → tier 0, but
Simple Demands: A Hop Along Tribute by Various Artists → tier 3.
Within the same tier, blended score breaks ties so more popular
albums by the same artist rank first.