GitLab

nix: add text-generation-benchmark to pure devshell

* nix: pure server and support both pure and impure devShells

* nix: remove unused poetry2nix input

It is not wired up and we now have a pure server.

* nix: add ipdb to impure devshell

Try to reduce the number of router/launcher rebuilds by filtering
sources. In this way, recompiles should only be triggered by changes
in Cargo or Rust files.