Rollup merge of #103575 - Xiretza:suggestions-style-attr, r=davidtwco

Change #[suggestion_*] attributes to use style="..."

As discussed [on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/336883-i18n/topic/.23100717.20tool_only_span_suggestion), this changes `#[(multipart_)suggestion_{short,verbose,hidden}(...)]` attributes to plain `#[(multipart_)suggestion(...)]` attributes with a `style = "{short,verbose,hidden}"` parameter.

It also adds a new style, `tool-only`, that corresponds to `tool_only_span_suggestion`/`tool_only_multipart_suggestion` and causes the suggestion to not be shown in human-readable output at all.

Best reviewed commit-by-commit, there's a bit of noise in there.

cc #100717 `@compiler-errors`
r? `@davidtwco`

compiler/rustc_passes/src/errors.rs

@@ -291,7 +291,7 @@ pub struct DocTestUnknownAny {
 #[note(no_op_note)]
 pub struct DocTestUnknownSpotlight {
     pub path: String,
-    #[suggestion_short(applicability = "machine-applicable", code = "notable_trait")]
+    #[suggestion(style = "short", applicability = "machine-applicable", code = "notable_trait")]
     pub span: Span,
 }