Integrate devenv support

[domenkozar]

Hey!

We're a huge fans of Zed at @cachix and I'd like to request integration of https://devenv.sh, especially since it supports 60+ languages.

We've started our bit to be able to specify LSP support for each language by default, so that users only need to do:

{
  languages = {
    rust.enable = true;
    python.enable = true;
  };
}

We're also going to soon replace direnv with our own Rust implementation, so it would be possible to leverage environment activation at Rust layer and integrate it into Zed.

I see there are two levels of integration:

1. if devenv.nix exists, provide tooling to the editor and activate the shell
2. if devenv.nix is missing, create one by default based on what the repo is using using ad-hoc environments

Then there's always ways to run tasks and running the processes.

[dlight]

Devenv can have LSP servers inside - Zed could use them instead of downloading its own LSP servers.

Anyway, maybe it's possible to provide at least partial devenv support in an extension? Not sure if an extension can provide tasks and the like.

[domenkozar]

See devenv 2.0 announcement for our Rust implementation of devenv reloading.

[blackfyre]

I've been gradually shifting away from VSCode to Zed and this would definitely be a boon!

[Malix-Labs]

I'm using devenv extensively, but I think if its support would came to Zed, it should only be an extension

And nix flake's devShells support should be higher priority

[blackfyre]

I'm fine with any supported format.