v0.7.0

Breaking changes

• YAML configuration files are no longer supported. TOML is the only configuration format;
  pyyaml is gone from the dependencies. A YAML config now fails with a clear parse error
  instead of being loaded. Migration: convert the flat job-name: {...} mapping into one
  [[job]] table per job, with the former key as name

Changed

• A broken or missing configuration file now reports a single error line naming the file
  and the problem, instead of dumping a traceback. Errors from the mailbox connection itself
  are still logged in full

• The configuration file name no longer matters: its content is always parsed as TOML, so a
  config may be called backup.job or anything else. copy previously rejected every file not
  named *.toml -- that restriction is gone, and copy accepts the same files as every other
  command

• mailvault is now on PyPI: install it with uv tool install mailvault (or pipx install
  / pip install) instead of pulling from the Git repository. The old name imapbackup was
  already taken on PyPI; mailvault was free, which is part of why the project was renamed.
  The package now carries the metadata a PyPI release needs (README as description,
  GPL-3.0-or-later license, project URLs) and is built with the uv_build backend