refactor(manager/custom): reorganize and update utility functions (#33050)

docs/usage/configuration-options.md

lib/modules/manager/custom/regex/index.ts

lib/modules/manager/custom/regex/strategies.ts

lib/modules/manager/custom/regex/utils.ts

lib/modules/manager/custom/utils.ts

lib/modules/manager/devcontainer/extract.ts

lib/workers/repository/extract/extract-fingerprint-config.ts

lib/workers/repository/update/branch/auto-replace.spec.ts