Auto merge of rust-lang#93511 - cjgillot:query-copy, r=oli-obk

Ensure that queries only return Copy types.

This should pervent the perf footgun of returning a result with an expensive `Clone` impl (like a `Vec` of a hash map).

I went for the stupid solution of allocating on an arena everything that was not `Copy`. Some query results could be made Copy easily, but I did not really investigate.

Author: bors