Add support to distinguish between diagnostics created by a reconciler and a builder

[dbaeumer]

Short summary: currently it is very hard to handle / merge diagnostics that come from to different source having the same owner. This either leads to stale problems or missing problems. For a lengthy discussion see #61140

Having support to distinguish between diagnostics create by a reconciler and a builder would help solve that problem.

[dbaeumer]

One idea would be two have two different tags that can be used. @jrieken & @mjbvz would that be in line with the current diagnostic design?

[mjbvz]

@dbaeumer Are you talking about the DiagnosticTag? I think that would make sense.

Or we could make it even more explicit by adding something like a creator?: 'builder' | 'task'| ... field on diagnostics

[dbaeumer]

@mjbvz yes I am talking about DiagnosticTag. The only disadvantage I see is that we need to search the array to determine whether a diagnostic is from a builder or a reconciler. Having a creator property would make this easier to distinguish.