Allow changing resource parameters without restarting via maintenance mode

Instead of requiring a restart to update parameter values, this procedure should be usable:
1. set maintenance mode for resource
2. change parameter
3. cleanup (to remove digest and force reprobe)
4. unset maintenance mode

The issue names no files or tests. Start by tracing the maintenance-mode, parameter-change, and cleanup command entry points, then verify that the listed sequence updates resource parameters, removes the digest, forces reprobe, and completes without a restart.

Written by the indexing model from the issue text.