The SSH retry matched connection words in any error output. When `mc alias set`
in a backup upload could not reach S3, its "connection refused" output caused a
retry of the full batch, and the second `docker run --name backup-of-<uuid>`
failed with a name conflict that hid the real error.
- Retry only SSH transport failures: exit code 255, or errors without an exit code.
- Keep the remote exit code on deployment command failures.
- Remove a leftover backup helper container in the same upload batch.
Closes#12059
instant_remote_process() applied its timeout only to Process::timeout(), while the shell-level timeout wrapper around ssh always used the global 3600s default, killing long backups and scheduled tasks at 1h with ssh exit code 255. Also applies the backup timeout to the S3 upload step and makes the default configurable via SSH_COMMAND_TIMEOUT.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Andras Bacsai