Update nixpkgs and GHC

Our nixpkgs is pinned. Newer nixpkgs have GHC 9.10+ and other goodies and changes and we want to keep up with them

* [ ] Investigate performance regressions with GHC 9.10
* [ ] Look into the state of TemplateHaskell on nixpkgs https://github.com/NixOS/nixpkgs/issues/275304
* There's some work that should alleviate these pain points going on in nixpkgs right now
* If needed, we can switch to building haskell on pkgsMusl + dependencies from pkgsStatic, this also can also yield a static binary. We use this trick in Echidna.
* [ ] Update nixpkgs with GHC 9.10
* Work ongoing in https://github.com/argotorg/hevm/pull/884
* Might need to jailbreak/fork aeson-optics to be able to build on Windows? Maintainer seems unresponsive

Start by locating the pinned nixpkgs configuration and reviewing the ongoing work in PR #884. Investigate the listed GHC 9.10 performance and TemplateHaskell concerns, then update nixpkgs and GHC once the Windows and static-build implications are understood; done means the project builds and its regressions are addressed.

Written by the indexing model from the issue text.