We have the trait at this point, so we can name it in the error
message, rather than using "Trait" as a (potentially confusing)
placeholder.

Thanks to Yuki "@JohnTitor" Okushi for pointing out where to look (in
the same file) for a closely related issue for ambiguous associated
types (as opposed to items; that was rust-lang#59225, except that one won't be
quite as easy to resolve, because we actually don't have the trait
`DefId` at that point).

…sdreavus

First question mark in doctest

We have had `?` for `Result`s in doctests for some time, but so far haven't used them in doctests. With this PR, I want to start the de-`unwrap`ping of doctests – and the discussion on where to do so.

There is one downside, which is that the code can no longer be copied into a plain `main()` method, on the other hand, there should be a workable error if one does this.

…QuietMisdreavus

Add missing links in Option documentation

r? @rust-lang/docs

…lacrum

rustbuild: Cleanup global lint settings

Lint settings do not depend on `if let Some(target) = target` in any way, so they are moved out of that clause.

Internal lints now respect `RUSTC_DENY_WARNINGS`.

Crate name treatment is cleaned up a bit.

cc rust-lang#61545 @flip1995
r? @Mark-Simulacrum

…_assoc_item, r=petrochenkov

name the trait in ambiguous-associated-items fully qualified suggestion

We have the trait at this point, so we can name it in the error message, rather than using "Trait" as a (potentially confusing) placeholder.

Thanks to Yuki "@JohnTitor" Okushi for pointing out where to look (in the same file) for a closely related issue for ambiguous associated types (as opposed to items; that was rust-lang#59225, except that one won't be
quite as easy to resolve, because we actually don't have the trait `DefId` at that point).

r? @petrochenkov