Tier A (same building) dropped cian listings tagged listing_segment='novostroyki'
even in delivered buildings where that tag marks owner resales/переуступки
(sale_type=free). Gated relaxation of the #1186 guard, Tier A ONLY: include
novostroyki rows iff the same house has secondary (vtorichka/NULL) listings AND
secondary_count >= primary_count — secondary-dominant signal of a delivered house.
Prevents a lone vtorichka + clustered developer-priced novostroyki from anchoring
on застройщик prices after MAD-clip drops the rare secondary (~27% overvaluation).
Pure-primary / primary-dominated houses keep the #1186 guard. Behind
estimate_sb_tier_a_allow_primary_if_secondary_present (default True).
Dedup duplicate active rows by (source, source_id) primary key (codebase canon,
namespaced id/url tags, source_url fallback) — collapses rows whose source_url
differs only by trailing slash / query-param (e.g. cian source_id=330047129 ×2).
Tier C / radius / asking_to_sold_ratio paths untouched. 84 unit tests pass.
