ownerdiff: CODEOWNERS for a git range

A developer released ownerdiff v0.3, a tool that maps changed paths in a git range onto CODEOWNERS and groups them by owner, with new -owner and -only-unowned filters for team-specific reviews and gap detection.

Monorepo PRs and agent sessions touch many teams. ownerdiff maps changed paths onto CODEOWNERS and groups by owner. No network. No LLM. go install github.com/SybilGambleyyu/ownerdiff/cmd/ownerdiff@v0.3.0 ownerdiff origin/main...HEAD ownerdiff -format markdown main..HEAD ownerdiff HEAD~5 -owner @platform one team's slice ownerdiff HEAD~5 -only-unowned CODEOWNERS gaps ownerdiff HEAD~5 -fail-unowned CI: exit 2 if unowned v0.3 adds -owner and -only-unowned filters so a platform team can review only their paths, or an audit can list unowned files without the rest of the noise. One-shot install with the rest of the kit: curl -fsSL https://raw.githubusercontent.com/SybilGambleyyu/review-kit/main/install.sh | bash gitdigest origin/main...HEAD -summary ownerdiff origin/main...HEAD lockglance -git origin/main...HEAD -summary