geocode() ran EKB-only local tiers (2a _geoportal_house_match on
ekb_geoportal_buildings, 2c _cadastral_house_match, 2d
_cadastral_forward_sync — all strictly EKB or EKB-dominated) BEFORE the
already oblast-aware external providers (Yandex/Nominatim via OBLAST66_BBOX
+ region cross-check, shipped in c0cbdc2f). _parse_street_house drops the
city, so any non-EKB oblast street+house that collides with an EKB building
(e.g. "проспект Ленина 1" exists in both Nizhny Tagil and EKB) short-circuited
to EKB coordinates.
Add _names_non_ekb_city() — reuses the existing SVERDLOVSK_OBLAST_CITIES
gazetteer (minus Ekaterinburg) and word-boundary matching from
_has_oblast_marker/_DISTRICT_PREFIXES — to detect when an address explicitly
names a different oblast city. Gate tiers 2a/2c/2d behind
`use_local_ekb = not _names_non_ekb_city(address)`; EKB/bare addresses keep
the exact same code path (byte-identical ordering/logic, only additive
gating). Non-EKB addresses fall straight through to Yandex/Nominatim, which
already handle oblast-wide geocoding correctly.
Verified gendesign_cad_buildings is 99.85% EKB-scoped (47043/47111 rows);
ekb_geoportal_buildings is 100% EKB by construction — gating loses no
meaningful local coverage for non-EKB cities.
Follow-up (not in this PR): geocode_cache has rows poisoned by the old
behavior (non-EKB addresses cached with EKB coordinates) — needs a purge.
720cee2c8e