Refactors a large set of CT update scripts to use the shared `create_backup`/`restore_backup` helpers instead of per-script manual copy/move logic. This removes duplicated backup code, temp-file cleanup paths, and inconsistent restore behavior while keeping data/config restoration in the correct order for build/deploy steps. Several update paths were also aligned to use `CLEAN_INSTALL=1` during release deploys, with minor message/comment tweaks where restore timing is important.