Don't suggest rewriting call if resolution was invalid

[compiler-errors]

Fixes #143008.

The suggestion to "try calling {ident} as a method" was eating the more relevant suggestion to mark the tuple struct's fields as pub so its ctor is visible.

See inline comment.

[rustbot]

r? @petrochenkov

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[compiler-errors]

This doesn't affect any other tests, so I just went with a simple heuristic here.

We could alternatively check if the path segment starts with a capitalized identifier, or match !matches!(res, Some(DefKind::Struct | DefKind::Variant)), or something? I think that's kinda overkill tho.

[petrochenkov]

The right condition here is probably res.is_none() || res.has_self_param().

Resolver already has the logic for res.has_self_param() in fn lookup_assoc_candidate in the same file, so it can probably be shared.

                            let has_self = match def_id.as_local() {
                                Some(def_id) => self
                                    .r
                                    .delegation_fn_sigs
                                    .get(&def_id)
                                    .is_some_and(|sig| sig.has_self),
                                None => {
                                    self.r.tcx.fn_arg_idents(def_id).first().is_some_and(|&ident| {
                                        matches!(ident, Some(Ident { name: kw::SelfLower, .. }))
                                    })
                                }
                            };