fix(useless_conversion): ignore From::from in generated code

[NicDevTV]

Summary

useless_conversion reported false positives for redundant From::from calls inside #[automatically_derived] implementations involving generic associated types.

This change skips that specific lint case for automatically derived code while preserving the existing behavior for regular code and other conversion methods. A regression UI test based on #17083 was added.

Testing

• cargo fmt --all -- --check
• git diff --check
• Targeted useless_conversion UI tests
• Full UI test suite
• Full ui-toml test suite
• Repository validation tests

The complete cargo test suite could not be run locally because some dependencies were unavailable in the offline environment.

changelog: [useless_conversion]: Avoid linting redundant From::from conversions in automatically derived implementations.

fixes #17083

[rustbot]

Thanks for the pull request, and welcome!

You should hear from one of our reviewers after this PR gets at least 2 reviews from the community.

Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (S-waiting-on-review and S-waiting-on-author) stays updated, invoking these commands when appropriate:

• @rustbot author: the review is finished, PR author should check the comments and take action accordingly
• @rustbot review: the author is ready for a review, this PR will be queued again in the reviewer's queue

[CommanderStorm]

Community review:

Code itsself is good, but on the tests this could be a bit cleaner to not "litter" 😉

View changes since this review

[CommanderStorm]

Community review: LGTM, but please squash the commits into one, so this does not take an review cycle 😉

View changes since this review

[NicDevTV]

like this @CommanderStorm ?

[CommanderStorm]

yes, tnx

[blyxyas]

Hello @NicDevTV, seems that an LLM assisted in this PR, we require disclosure as per the LLM policy

[NicDevTV]

@blyxyas Yes, I used an LLM while working on this PR. I used it to help me understand parts of the codebase and to explore a possible solution approach. I reviewed and understood the approach myself and implemented the actual changes on my own.