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
besendorf