chore: prepare v0.1.2 maintenance release

[roli-lpci]

Summary

• align package, citation, Zenodo, and changelog metadata on 0.1.2
• record the previously published 0.1.1 metadata release and the accumulated public-surface maintenance since it
• add an environment-bound, tag-checked, immutably pinned PyPI workflow

No parser, scanner, coverage, verdict, or exit-code behavior changes.

Verification

• 9 tests passed
• Ruff passed
• actionlint and high-severity Zizmor checks passed
• CFF and Zenodo metadata validated
• 0.1.2 wheel and sdist built; Twine checks passed
• fresh wheel reported 0.1.2 and its CLI help loaded

This PR does not create a tag, GitHub release, or PyPI publication.