- Document wildcard scope policy in ClientRegistry class docstring
- Add hostname None guard and IPv6 loopback (::1) to redirect URI validation
- Simplify redirect URI scheme validation into single guard clause
- Add try/finally cleanup to DCR client deletion test
- Validate 302 Location header in unknown client rejection test
- Add unit tests for IPv6 loopback, malformed URIs, and DCR proxy paths
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>