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## Summary
This PR adds a new `PyFormatOptions` struct that stores the python formatter options.
The new options aren't used yet, with the exception of magical trailing commas and the options passed to the printer.
I'll follow up with more PRs that use the new options (e.g. `QuoteStyle`).
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## Test Plan
`cargo test` I'll follow up with a new PR that adds support for overriding the options in our fixture tests.
This moves all docs about benchmarking and profiling into
CONTRIBUTING.md by moving the readme of `ruff_benchmark` and adding more
information on profiling.
We need to somehow consolidate that documentation, but i'm not convinced
that this is the best way (i tried subpages in mkdocs, but that didn't
seem good either), so i'm happy to take suggestions.
