stalld v1.27.1

  Behavior changes:

  * Make syslog logging opt-in by default
    Syslog is now disabled by default; use -s/--log_syslog to enable.
    The systemd service file has been updated to preserve existing behavior.

  * Die on invalid CPU affinity
    stalld now exits with an error on invalid -a/--affinity arguments
    instead of silently ignoring them.

  Test infrastructure:

  * 33 commits improving test reliability with event-driven detection,
    new helper functions, and bug fixes.