Allow use of appName/s instead of entity IDs

[ghost]

Feature Description

We would like to use the appName instead of the entity ID for the alert conditions.

We are looking at using this operator to manage our per-application alerts. The trick we have is that we do not know the Entity ID for the application and it is hard to get (especially before the application begins reporting).

Describe Alternatives

We could start reporting random data to the appName and then ping the API get the Entity ID. After this we would need to dynamically provision the Alert Condition resource with the Entity ID. It would be better if the Entity IDs (or appName/s) could be read via a ConfigMap or something else more dynamic.

Additional context

Any other ideas? This is a little difficult to manage.