release(v4.9.1): tests no longer reach a real herdr server - archive the review reports and bump the lockstep version

Review loop (--review-only, --all-reviewer): round 1 (@325b056) 4/4 PASS,
round 2 (@db7f4ca, HERDR_SESSION) 4/4 PASS. Full suite at 325b056 on
macOS / Python 3.9 / bash 3.2 / herdr 0.9.3 from an agent pane:
1845 passed / 0 failed / 56 skipped (18 test_deploy_freshness skips: no
nats-docker submodule in the fresh worktree); the panes of the real
servers (default, multi-agent-mux) and ~/.claude/projects were unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VCgu9Fa9iT7TbJUSzdq4Ff

README.md

@@ -2,7 +2,7 @@
 
 An advanced, high-reliability **Multi-Agent Orchestration & Messaging Backplane** framework built on Herdr and MQTT. It is designed to coordinate, isolate, and audit long-running agent tasks (such as code generation, refactoring, and security reviews) across multiple LLM backend clients (`claude`, `agy`, `hermes`, `grok`, `opencode`, `codex`).
 
-[![Version: v4.9.0](https://img.shields.io/badge/version-v4.9.0-blue.svg)](VERSIONS.md)
+[![Version: v4.9.1](https://img.shields.io/badge/version-v4.9.1-blue.svg)](VERSIONS.md)
 
 ---