ci(bind): require current package description

[bryanwieg]

Summary

• update the BIND plugin changelog through 1.36
• require pkg-descr updates for publishable runtime, package-hook, and package-metadata changes
• support both direct master PRs and reusable release-branch checks without moving-base races
• exempt test-only changes and PLUGIN_REVISION-only rebuilds

Validation

• 320 CI-helper tests and 3 subtests passed
• focused guard/workflow suite: 18 passed
• shell syntax, Python compilation, and git diff checks passed
• independent correctness, simplification, test-value, security, and documentation review completed