Get pacemaker default value from pacemaker-schedulerd metadata

To get the default value for most commonly used parameters, like `stonith-timeout`,
it will be reliable to fetch and parse these value from `usr/libexec/pacemaker/pacemaker-schedulerd metadata`

Start by locating the code that handles commonly used parameter defaults and inspect the output of usr/libexec/pacemaker/pacemaker-schedulerd metadata. Determine how values such as stonith-timeout can be fetched and parsed, then verify that the resulting defaults are used reliably for the relevant parameters.

Written by the indexing model from the issue text.