houses.year_built is only 38% filled and material_walls 0%. The existing ГИС-ЖКХ
loader already populates houses.zhkh_year (70%) but never copies it into
year_built — that's the core gap. Adds a ДОМ.РФ капремонт open-data loader
(КР1.1 house registry + КР1.2 constructive elements, region 66) into a new
domrf_kapremont staging table, then backfills houses.year_built/material_walls/
total_floors via COALESCE(existing, domrf, zhkh_year) — folding in the
already-loaded ЖКХ year so houses without a ДОМ.РФ match still benefit — and
propagates houses.year_built into listings.year_built for still-NULL rows so
the estimator's year_built cohort filter runs on real years across all sources
(avito 0%→~36-52% once linked houses gain a year). Supersedes the parked
cohort-exclusion PR #2474.
