fix: don't suggest .into_iter() for .cloned()/.copied() on owned items

[RafeSymonds]

Issue: #151147
Prevents the compiler from suggesting IntoIterator when .cloned() or .copied() is called on a collection that doesn't contain references. This avoids misleading suggestions where the fix would still result in a type error.

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[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[lcnr]

I disagree with this help message. We should not suggest to remove cloned here. Maybe the user wanted to clone the option to avoid incorrectly moving it.

I do agree that we should improve impl_into_iterator_should_be_iterator to not suggest into_iterator if the following method is actually still incorrect. In a sense, we should strengthen impl_into_iterator_should_be_iterator to check all unsatisfied predicates, instead of always returning yes for a single self: Iterator one

[reddevilmidzy]

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[rust-bors]

☔ The latest upstream changes made this pull request unmergeable. Please resolve the merge conflicts.