chore: update toolchain and fix lint errors

[aqrln]

• Update Nix flake
• Update Rust to 1.82.0
• Fix compiler warning for unused errors on Rust 1.81 (we keep those on purpose for documentation purposes)
• Fix deprecation warning on Rust 1.82
• Fix clippy warnings
• Update wasm-bindgen to match the version in Nix
• Update WASM toolchain to nightly-2024-09-01 (corresponds to Rust 1.82.0)

[github-actions]

WASM Query Engine file Size

Engine	This PR	Base branch	Diff
Postgres	2.038MiB	2.063MiB	-26.582KiB
Postgres (gzip)	819.666KiB	824.207KiB	-4.542KiB
Mysql	2.004MiB	2.034MiB	-31.083KiB
Mysql (gzip)	805.711KiB	812.031KiB	-6.320KiB
Sqlite	1.902MiB	1.929MiB	-27.699KiB
Sqlite (gzip)	765.805KiB	770.618KiB	-4.813KiB

[codspeed-hq]

CodSpeed Performance Report

Merging #5022 will not alter performance

_{Comparing rust-1.81 (df2376a) with main (b9903dc)}

Summary

✅ 11 untouched benchmarks

[aqrln]

?Sized bound was useless because ExternalInitializer<'_> requires Sized

[jkomyno]

The bundle size reduction in Wasm is a nice surprise!

[aqrln]

The bundle size reduction in Wasm is a nice surprise!

Not really a surprise, this consistently happens every time we update the WASM toolchain. That's the compiler's job, to optimize code better, it should always be becoming ever faster and/or smaller, especially with LLVM updates.

[aqrln]

That's why we shouldn't be forgetting updating it 😉