Get a list of baseURLs that are enabled/disabled for specific handlers

**Is your feature request related to a problem? Please describe.**
We have an API that returns the latest version of configuration that includes enabled/disabled sites/orgs for specific handlers.
However, most of the time the consumers are more interested in the baseURLs than the siteIds.

**Describe the solution you'd like**
Get a list of baseURLs that are enabled/disabled for specific handlers, either via API or Slack command.

**Additional context**
https://cq-dev.slack.com/archives/C05A45JBP9N/p1724255406662579?thread_ts=1724245128.689439&cid=C05A45JBP9N

Start by tracing the existing API that returns configuration with enabled and disabled site or organization IDs, then inspect how handler-specific data is exposed. Compare an API response with a Slack command as the possible entry point. Done means consumers can retrieve the corresponding baseURLs for enabled and disabled handlers.

Written by the indexing model from the issue text.