fix(sql): restore partial predicate on 5 listings indexes (#1398)

097_index_hygiene.sql de-partialized 5 listings indexes on the false premise
that is_active=100% true. 104_index_hygiene_geom_dedup.sql acknowledged the
premise is stale (49% active on prod, 2026-06-13) but only cleaned up the
redundant geom duplicate, leaving 3 composite indexes full.

Restore WHERE is_active=true on the composite hot-path indexes:
- listings_active_filter_idx (rooms, price_rub, area_m2, scraped_at DESC)
- listings_house_price_idx   (house_id_fk, price_rub)
- listings_rooms_area_idx    (rooms, area_m2)

Excluded: listings_geom_active_idx (dropped by 104, listings_geom_idx covers it),
listings_scraped_desc_idx (not in issue #1398 suggested fix scope).

CONCURRENTLY not used — migration runner wraps in BEGIN/COMMIT (see 117 note).

tradein-mvp/backend/data/sql/120_restore_partial_active_indexes.sql

@@ -0,0 +1,68 @@
+-- 120_restore_partial_active_indexes.sql
+-- Fixes #1398: restore WHERE is_active = true predicate on 3 composite listings indexes
+-- that were de-partialized by 097_index_hygiene.sql on the false premise that
+-- is_active is 100% true.  104_index_hygiene_geom_dedup.sql explicitly acknowledges the
+-- premise is stale (prod 2026-06-13: 19312 active / 39115 total, ~49% active), but
+-- only dropped the redundant geom duplicate -- the composite indexes were left full.
+--
+-- Indexes restored with WHERE is_active = true predicate:
+--   1. listings_active_filter_idx  (rooms, price_rub, area_m2, scraped_at DESC)
+--   2. listings_house_price_idx    (house_id_fk, price_rub)
+--   3. listings_rooms_area_idx     (rooms, area_m2)
+--
+-- These indexes directly back the estimator hot-path (estimator.py _COMMON_WHERE:
+--   AND rooms = :rooms  AND area_m2 BETWEEN ...  AND is_active = true  AND price_rub > 0)
+-- and asking_to_sold_ratio.py, which always filters is_active = true.
+-- Restoring the predicate excludes ~51% inactive rows from the index, making it
+-- roughly half the size and allowing index-only scans on active-only queries.
+--
+-- Excluded from restore:
+--   listings_geom_active_idx  -- dropped by 104 as exact dup of listings_geom_idx
+--                                (keep listings_geom_idx as the single full GIST)
+--   listings_scraped_desc_idx -- simple recency sort not in hot-path composite filters;
+--                                issue #1398 suggested fix does not include it
+--
+-- Note on CONCURRENTLY:
+--   NOT used here. The deploy migration runner wraps each file in an explicit
+--   transaction (BEGIN/COMMIT). CREATE INDEX CONCURRENTLY cannot run inside a
+--   transaction block. At ~40k rows the ACCESS EXCLUSIVE lock is sub-second.
+--   See migration 117_listings_last_seen_deactivate_index.sql for the same rationale.
+--
+-- Idempotency:
+--   DROP INDEX IF EXISTS + CREATE INDEX IF NOT EXISTS -- safe to re-run.
+--
+-- Dependencies: 002_core_tables.sql, 050_search_optimization.sql,
+--               097_index_hygiene.sql (de-partialized these indexes),
+--               104_index_hygiene_geom_dedup.sql (acknowledges stale premise)
+-- Deploy order: standalone, apply any time after 097 + 104.
+
+BEGIN;
+
+-- 1. listings_active_filter_idx
+--    Original (050_search_optimization.sql:52):
+--      ON listings (rooms, price_rub, area_m2, scraped_at DESC) WHERE is_active = true
+--    097 stripped the predicate. Restoring it.
+DROP INDEX IF EXISTS listings_active_filter_idx;
+CREATE INDEX IF NOT EXISTS listings_active_filter_idx
+    ON listings (rooms, price_rub, area_m2, scraped_at DESC)
+    WHERE is_active = true;
+
+-- 2. listings_house_price_idx
+--    Original (050_search_optimization.sql:57):
+--      ON listings (house_id_fk, price_rub) WHERE is_active = true
+--    097 stripped the predicate. Restoring it.
+DROP INDEX IF EXISTS listings_house_price_idx;
+CREATE INDEX IF NOT EXISTS listings_house_price_idx
+    ON listings (house_id_fk, price_rub)
+    WHERE is_active = true;
+
+-- 3. listings_rooms_area_idx
+--    Original (002_core_tables.sql:58):
+--      ON listings (rooms, area_m2) WHERE is_active = true
+--    097 stripped the predicate. Restoring it.
+DROP INDEX IF EXISTS listings_rooms_area_idx;
+CREATE INDEX IF NOT EXISTS listings_rooms_area_idx
+    ON listings (rooms, area_m2)
+    WHERE is_active = true;
+
+COMMIT;