Validate configured systemd units before applying service-specific DH
parameter synchronization.
Synchronize per-service DH parameters before restarting active units. Query
system-wide and per-user systemd managers with LoadState, ActiveState,
SubState, and Type.
Restart active units, start inactive or failed Type=oneshot units, and leave
inactive or failed non-oneshot units without a service action. Skip missing
units, unavailable user managers, and invalid or incomplete service
definitions without creating misleading synchronization messages.
Add robust error handling for DH parameter generation, permission changes,
directory creation, global synchronization, and temporary file cleanup.
