The package version now comes from the latest v* git tag, so a release
is a tag and nothing else. A scheduled workflow tags main on the first
of the month when something was merged since the last release, creates
the GitHub release with generated notes, and publishes to PyPI and the
container registry. Pushing a v* tag by hand goes through the same path.
The dependency switch from betterproto to betterproto2 was incomplete.
This updates all affected files to use the betterproto2 API:
- tombstone.py: rewrite generated code to use betterproto2.field() with
explicit TYPE_* constants, repeated/optional/group flags, and map_meta()
for map fields
- tombstone_crashes.py: update import and fix to_dict() call to use
keyword-only casing= argument required by betterproto2
- pyproject.toml: replace betterproto[compiler] dev dep with betterproto2-compiler
- Makefile: update protoc plugin flag to --python_betterproto2_out