- Change DB backup helpers to return whether a dump was actually produced
- Detect DB containers without successful dumps in --dump-only mode
- Fallback to file backups with a warning instead of skipping silently
- Refactor DB dump logic to return boolean status
- Add E2E test covering dump-only fallback when databases.csv entry is missing
https://chatgpt.com/share/6951a659-2b0c-800f-aafa-3e89ae1eb697
