burst() entry nodes: selectDiverseSeeds' type-diversity bonus silently evicts higher-scoring seeds from the top-5

An integration test (void-provenance) seeded Problem nodes matching a nonsense token, then called burst({query}) and asserted the seeded nodes appear in result.entries. All 3 tests failed: the seeded nodes were absent from entries despite being high-ranked candidates. Initial hypothesis was that they were OUT-RANKED out of the candidate pool (keyword-only leg has a hard score ceiling of KEYWORD_BONUS_CAP=0.6, while embedded catalog nodes get a 1.2x short-term novelty tierBoost). That hypothesis was REFUTED by instrumentation.