Release v7.86.0

Added

• cratis-engineering-consolidation-guard skill: when folding several pull requests into one, re-landing reverted work or restoring commits by cherry-pick, prove nothing was dropped — per-commit pairing by patch-id and range-diff, per-file content checks that catch merge resolutions which revert or lose files, and a specification-file ratchet. Ships a portable verify-consolidation.sh (with --discover and --self-test) and the pattern for running it as a required pull request check, with accepted losses recorded as commit trailers. (#413)
• A GitHub Copilot plugin.json at .cratis/ai, so the Cratis skills can be submitted to github/awesome-copilot. Its version is the plugin manifest version, kept equal to the marketplace manifests by corpus verification. (#503)

Changed

• The pull request rule's guidance on grouping related changes now points to the consolidation guard. (#413)