fix(issue-6): fail-closed registry timeout and TUI turn handshake

- Introduce finalize_unfinished in multi-agent-mux-delegate-job for fail-closed atomic transitions
- Enforce CAS dispatch_token and attempt_id pinning across engine, CLI, and lifecycle scripts
- Integrate Herdr wait_for_agent_idle turn handshake to prevent prompt loss and race conditions
- Resolve bash 3.2 set -u empty array expansion compatibility in lib.sh
- Preserve Issue #5 R2 contract in CAS transition engine (engine.py, publish_event.py, service.py)
- Add comprehensive regression suites (test_issue6_fail_closed.py, test_issue6_turn_handshake.py)
- Bump lockstep framework and skills to v4.4.1 across lib.sh, eager.py, VERSIONS.md, 8 SKILL.md
- Synchronize documentation (IMPROVEMENTS.md, MESSAGING.md, state-transitions.md, task.md, phase5-e2e.md)
- Unanimous PASS achieved across 4 reviewer team leaders (Claude, Codex, OpenCode, Grok)

Closes #6

.agents/skills/lib_py/delegation/cli.py

@@ -39,6 +39,8 @@ def _build_parser() -> argparse.ArgumentParser:
     p_pub.add_argument("--retained", action="store_true")
     p_pub.add_argument("--registry-dir", default=None)
     p_pub.add_argument("--attempts", type=int, default=3)
+    p_pub.add_argument("--expect-dispatch-token", default=None)
+    p_pub.add_argument("--attempt-id", type=int, default=None)
     p_pub.add_argument("-v", "--verbose", action="store_true")
 
     p_daemon = sub.add_parser("ensure-daemon", help="start the subscriber daemon if absent")
@@ -68,6 +70,10 @@ def main(argv: Optional[List[str]] = None) -> int:
             forward += ["--retained"]
         if args.registry_dir:
             forward += ["--registry-dir", args.registry_dir]
+        if args.expect_dispatch_token:
+            forward += ["--expect-dispatch-token", args.expect_dispatch_token]
+        if args.attempt_id is not None:
+            forward += ["--attempt-id", str(args.attempt_id)]
         if args.verbose:
             forward += ["--verbose"]
         return publish_event.main(forward)