Add the brief use case UC-006 (Release a Reusable Workflow), the use case in
UCD-001, stories US-001.11 to US-001.13 and ADR-0006: one version for the
repository with SemVer tags and a moving major tag, a release only from a
green commit with a changelog entry, consumers pin the major or an exact tag
and never main. Add the maintainers' checklist guides/release-process.md.
Review and accept them (RC-040 to RC-043), update TM-001 and the registry.
Task: MIL-004#1
Tirsvad