Tweak output of import suggestions

When both `std::` and `core::` items are available, only suggest the
`std::` ones. We ensure that in `no_std` crates we suggest `core::`
items.

Ensure that the list of items suggested to be imported are always in the
order of local crate items, `std`/`core` items and finally foreign crate
items.

Tweak wording of import suggestion: if there are multiple items but they
are all of the same kind, we use the kind name and not the generic "items".

Fix #83564.

Author: estebank

tests/ui/crashes/ice-6252.stderr

@@ -4,9 +4,7 @@ error[E0412]: cannot find type `PhantomData` in this scope
 LL |     _n: PhantomData,
    |         ^^^^^^^^^^^ not found in this scope
    |
-help: consider importing one of these items
-   |
-LL + use core::marker::PhantomData;
+help: consider importing this struct
    |
 LL + use std::marker::PhantomData;
    |