Two parts, both of which could be in a properties sheet for a script (or other methods).
1) script last edit date. Revision control would be far easier if you knew which scripts were touched when (and ideally, by who, for team development).
2) attached to each script, a properties list of everyplace that script has been assigned from. As you have to select the script from an FM dialog, to attach to a button, field, layout - any objects - the information is there - should be relatively easy. If this were written to a script properties sheet when added (deleting would be tougher to track, but necessary - maybe an update on exit, or a manual execute update option? to clean up deletes), then it would be far easier that the time consuming DDR effort to extract that information, and could be seen within script workspace.