Improved Policies Dashboard for compliance monitoring

Hi!

Currently the policies dashboard allows us to check where policies are applied and to check the last sampled policy runs. This is important for plan policies, as we use them to enforce guidelines.

It is hard to link a given policy to the stacks where it evaluated to a warning or deny.

We would like to improve this dashboard to be able to have an overview of the compliance state of different stacks. When clicking on a plan policy, we would like to get the list of stacks where the policy evaluates to Pass, Warn or Deny.

We would also like to get a global overview across all the plan policies of the number of stacks with their different evaluation results and the possibility to drill down into them.

We also would like to be able to export the policy evaluation result to be able to centralize them in our SIEM tool. This is especially valuable as we have several Spacelift instances running independently.