Improve Policies overview page and show where exactly the policy is used

Currently the policies overview page just shows if an existing policy is used or not.
And if used - how often it is used.

it would be much more valuable if the page would
- list not only how often a policy is used, but instead show where exactly it is used
- give a possibility to directly jump to the usage of the policy, for configuring
- have a filter possibility to list all unused policies, maybe via an explicit filter button

**Describe alternatives you've considered**
- the page has a filter/search option, but only searching for the policy name is possible

**Additional context**
Add any other context or screenshots about the feature request here.