feat: explain reference freshness and usage before updating or retiring guidance #145

Summary

Please help users decide whether operational guidance should be refreshed, preserved as history, or retired by showing both its current accuracy and where it is still used.

Problem or workflow

Old instructions may still be correct, and apparently unused guidance may support another workflow. Treating age or a limited search as proof that something is obsolete can remove useful knowledge or break dependent instructions.

Affected area

Documentation maintenance, reference checking, and provenance review.

Proposed behavior

Extend the existing documentation and provenance workflows to distinguish confirmed inaccuracies, material due for review, preserved historical records, and unresolved questions. Show which instructions or workflows rely on a reference and explain the limits of the search when no uses are found. Give a reasoned recommendation before content is changed or retired, while preserving meaningful historical evidence.

For example, a small business reviewing an old service guide should be able to see whether it still supports an active recovery procedure before removing it.

Related: #65 and #67. The emphasis here is safe review and retirement decisions, including downstream usage, rather than adding more freshness metadata.