The plugin cache is keyed by version (cache/mroberts/guards/<version>), so
'claude plugin update' reports 'already at the latest version' and skips the
reinstall whenever content changes without a version bump. The marketplace
clone had fetched the new commit; the cache never saw it.
Registers five inert probe entries covering the 2x2 of timeout and
statusMessage on PreToolUse:Bash, plus a PostToolUse statusMessage cell.
Each probe is in its own matcher block so a dropped entry cannot take
the others with it, and logs its identity before reading stdin so a
failed dispatch stays distinguishable from a failed payload read.
The real bash-guard entry is unchanged and serves as the control.
mroberts