Refine mode: production diagnostic output

[lennartkats-db]

Changes

This refines the mode: production diagnostic output now that the Detail property is rendered as output. This is a follow-up to #1712.

[lennartkats-db]

@pietern I'd really like to include location information here and in the other diagnostics in this file, but I'm not sure there is any good way to do that without reverting 6ea5306 (which was originally discussed in #1712 (comment))

[pietern]

Which location do you want to include?

The conditional checks for absence, so the best possible location seems to be the target definition itself?

If the variables v2 proposal from @denik materializes, we can revisit access to the original targets section. The comment I made in that thread still holds now.

[lennartkats-db]

Yeah, I'd just include the target block as seen in 9466bdc. The same would apply to a couple of the other messages in process_target_mode.

So it seems that the location information would be another benefit of decomposing select_target. We may care more about that in a later stage of the current workspace work. I think we covered all the other trade-offs in the other thread.

Variable resolution is a good point though — it seems like we would want to resolve variables for the selected target. And we could preemptively clean up the other targets to avoid confusion.

In any case, I'd be okay to merge this as is for now. With the extra comments, the surprises of select_target are somewhat alleviated. And we can do without location information for now.

[lennartkats-db]

Note that tests currently fail here; I'll do another quick pass over this based on the outcome of the discussion above.

[pietern]

Please consider adding an acceptance test for these conditions. That will ensure that the advice is rendered correctly in the expected cases.