1.2.12

The package finishes becoming cronstable. Everything that was still
named yacron2 -- the import package, the python -m entry point, the
console-script command, and the PyPI distribution -- is now cronstable, so
the name is consistent all the way from pip install through import to the
CLI. The fork has shipped as cronstable in its repo and docs for a while;
this release moves the code's own identifiers to match, so nothing user-facing
still answers to the old name.

• The yacron2 package is renamed to cronstable. The source tree moves
  from yacron2/ to cronstable/ and every intra-package import follows, so
  import yacron2... becomes import cronstable... and python -m yacron2
  becomes python -m cronstable. The web assets, backends, and cluster
  modules move with it; no module contents change, only their home.

• The CLI command and PyPI distribution are renamed. The console script the
  wheel installs is now cronstable (it was yacron2), and the project
  publishes to PyPI as cronstable -- pip install cronstable. The repo,
  Docker image, and container registry are ptweezy/cronstable. Update any
  scripts, service/unit files, or pip/import references that still say
  yacron2; there is no compatibility shim, so the old names stop resolving.

• Release-pipeline hardening. The release workflow now pushes the version
  tag with a scoped RELEASE_TOKEN rather than the default GITHUB_TOKEN --
  GitHub refuses to let the Actions app push a tag whose commit touches
  .github/workflows/ without the workflows scope it cannot be granted -- and
  the PyPI publish runs with skip-existing, so a release interrupted after the
  upload (before the tag and GitHub Release) can be retried without burning the
  version.

Full Changelog: 1.2.11...1.2.12