chore: Normalize imports style

[Veykril]

Effectively reformatted everything with

imports_granularity = "Module"
group_imports = "StdExternalCrate"
reorder_imports = true

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[codspeed-hq]

CodSpeed Performance Report

Merging #779 will not alter performance

_{Comparing Veykril:veykril/push-npsmszmlrsql (4e00670) with master (20a347e)}

Summary

✅ 12 untouched benchmarks

[MichaReiser]

How do we plan on preserving this format style in the future or are we okay if the import style denormalizes over time?

[Veykril]

Great question, the main annoyance is that the rustfmt configs are still unstable 🙃 rust-analyzer will attempt to keep the ordering and style consistent (unsure if RustRover has a similar thing going on). I think it is fine if the style degrades over time, we can always do another one of these PRs every now and then, but right now imports are fairly chaotic.

[Veykril]

Also I picked imports_granularity = "Module" given it reduces git conflicts between PRs to some extent. The option here is up to debate.

[davidbarsky]

For "I hate resolving conflicts" and "trivial git blame" reasons, I'd personally vote for imports_granularity = "Item", but I know the format is extremely ugly controversial 😅