-- Tables affected: qt_configurations
-- recovery.not-started: check first; ADD COLUMN fails if app_version already exists
-- recovery.partial: ALTER TABLE qt_configurations DROP COLUMN app_version;
-- recovery.completed: no action needed
-- verify: app_version column missing | SELECT 1 FROM information_schema.COLUMNS WHERE table_schema=DATABASE() AND table_name='qt_configurations' AND column_name='app_version' HAVING COUNT(*)=0

-- Track application version used for configuration writes (create/update via sync)
ALTER TABLE qt_configurations
    ADD COLUMN app_version VARCHAR(64) NULL DEFAULT NULL AFTER owner_username;