feat: adopt flakes

[teto]

I was trying to contribute to nc4nix but prefer flakes. Flakes make this even more reproducable.

I "flakified" the repo with gomod2nix.
The update removed delve libcap from shell.nix , but go build works without it ?

The stuff in default.nix I am not sure what it's about
I dont develop in go, go run seemed like the good command to start nc4nix but it does nothing both on main and in this branch ?

[leonklingele]

@Conni2461 can you please have a look at this? :)

[cheriimoya]

Neither nix build nor nix-build are going through:

@nix { "action": "setPhase", "phase": "unpackPhase" }
unpacking sources
unpacking source archive /nix/store/ndsndqv0669y5y79fc7d8g6z040i61id-s2885l2hgi8i5qa91vzyvnwj93sxzrnq-source
source root is s2885l2hgi8i5qa91vzyvnwj93sxzrnq-source
@nix { "action": "setPhase", "phase": "patchPhase" }
patching sources
@nix { "action": "setPhase", "phase": "updateAutotoolsGnuConfigScriptsPhase" }
updateAutotoolsGnuConfigScriptsPhase
@nix { "action": "setPhase", "phase": "configurePhase" }
configuring
@nix { "action": "setPhase", "phase": "buildPhase" }
building
Building subPackage .
go: finding module for package github.com/hashicorp/go-version
main.go:14:2: cannot query module due to -mod=vendor

Only nix-shell works for me.
Do I need to run anything else or add some parameters?