docs: correct recovery lineage public facts

[dormitivegit]

Summary

• align the recovery-lineage status block with the current product and distribution versions
• identify the rc5/rc6 publications as historical artifacts and update repository links
• add a regression assertion binding the documented status block to the runtime constants

Scope

This PR changes only docs/RECOVERY_LINEAGE.md and
tests/test_repository_surface.py. It does not change runtime code, public
contracts, version sources, release artifacts, tags, or PyPI state.

Verification

PYTHONDONTWRITEBYTECODE=1 PYTHONPATH=src \
  python3 -m unittest discover -s tests -v

Result: 327 tests passed, 0 failed.

Compatibility and security

Documentation and regression-test change only. No runtime compatibility,
migration, distribution, or security behavior changes.