Fix an indefinite CLI shutdown after the first monitor health-check tick. The health loop already held its mutex when it called public alert methods that attempted to lock it again. Internal alert helpers now reuse the held lock, while public methods retain their own locking.
The patch covers successful checks, repeated critical failures and alert recovery. Regressions exercise the actual timer and Stop; a real CLI run past the default 30-second interval then exited normally after SIGTERM. Full core, CLI, API, driver compatibility, static analysis and reachable-vulnerability checks passed.
Install the patch with npm install -g argonctl@2.1.1, update the existing Homebrew formula with brew upgrade argon-lab/tap/argonctl, or download a platform binary below and verify it against SHA256SUMS.
The v2.1.0 tag and assets remain unchanged.