PR #500 added 035_drop_duplicate_indexes.sql to drop listing_sources_listing_idx2
and houses_geom_idx2, but 050_search_optimization.sql re-CREATED them on every
deploy (sort order: 035 DROP → 050 CREATE). End state: dupes restored.
Verified on prod 2026-05-24 ~12:08 via docker exec tradein-postgres psql.
Fix: remove the two CREATE INDEX statements from 050 at the source. After this
PR, deploy order becomes: 035 DROPs (succeeds on existing dupes) → 050 doesn't
recreate → final state matches PR #500's intent.
Migration 035 retained as the durable DROP guard.
