DNS should say what's wrong

It should list what's conflicting. Might have to do with the trailing dot on the CNAME, but not sure. My DNS kept stripping it on save:

I gave up for now and reverted my DNS settings.

Start by reproducing the DNS save flow described, including a CNAME with a trailing dot, and inspect the attached screenshot for the reported conflict. No repository entry point or test is named; done means the error identifies the conflicting records and the saved trailing-dot case is handled.

Written by the indexing model from the issue text.