Merge flake.nix

[DieracDelta]

This PR removes the libp2p-networking flake.(nix|lock) and moves the useful pieces from this flake into the rootflake.nix. Notably:

• Nix shell to compile static binaries with musl
• Nix shell with performance tooling (grcov, flamegraph, nightly cargo)
• Programmatic generation of check and package attributes for all members of the workspace
• Overrides for protobuf (needed on aarch64-darwin and perhaps linux)

[VictorKoenders]

I get this error running nix-shell in the phaselock folder:

error: a 'aarch64-linux' with features {} is required to build '/nix/store/ni2xlnpykcfhx7y48y7y30p30hd3682z-camino-1.0.4.tar.gz.drv', but I am a 'x86_64-linux' with features {benchmark, big-parallel, kvm, nixos-test}

[DieracDelta]

This "should" work (it works for me on darwin). Turns out // was forcing all derivations to be evaluated which requires target-triple specific features b/c of IFD. The fix is to manually hard code in the checks/packages directly. No idea why dontRecurseIntoAttrs doesn't work here...

[DieracDelta]

It's probably fine to ignore the CI complaints since these are fixed in #35