NSPD quarter-dump territorial_zones (layer 875838) does NOT store ПЗЗ letter
codes in properties — zone_code receives the cadastral reg number ("66:41-7.14")
or None, never a "Ж-1" style code. The old prefix check (startswith "Ж-"/"Ж1" …)
therefore never matched real NSPD data, silently marking every dump-sourced parcel
as non-residential (PZZ_NOT_RESIDENTIAL blocker).
Fix: three-tier detection in is_residential_zone:
1. Regex ^Ж on zone_code — handles PKK6/pzz_zones_ekb sources ("Ж-1", "Жс")
2. NSPD subcategory from raw_props — subcategory=2 (Жилые зоны, 221 ЕКБ objects)
and subcategory=3 (Смешанное использование, 126 objects) → residential;
subcategory=1 (ИЖС) excluded — МКД not permitted there
3. zone_name substring "жил" — fallback for non-standard sources
compute_gate_verdict now passes nspd_zoning["raw_props"] to is_residential_zone.
