main
fix: replace placeholder verification queries with real checks
feat: convert Russian text to English in mysql.ts and mongodb.ts (names, cities, products, sample solutions)
feat: expand SQL adapter coverage (PostgreSQL EXTRACT/DATE_TRUNC/INTERVAL/GENERATE_SERIES, MySQL JSON_ARRAYAGG/REGEXP/GROUP_CONCAT SEPARATOR, ClickHouse formatDateTime fix)
fix: make DDL/FTS5 tasks work end-to-end
feat: configure Amvera Cloud deployment & fix remaining TypeScript errors