Simplify integration with flakes/access to inputs in "treefmt.nix"

[SebTM]

Is your feature request related to a problem? Please describe.

It would be nice / easier / cleaner if the integration would not require to define custom-functions. It was a hassle to adjust the treefmtEval function to pass-through inputs to be able to use a package from input, maybe this can be adjusted that all arguments like on imports/modules can be used automatically:

      treefmtEval = eachSystem (pkgs:
        treefmt-nix.lib.evalModule pkgs (import ./treefmt.nix {
          inherit nixfmt;
          system = pkgs.system;
        }));

Describe the solution you'd like

Maybe they can be provided by treefmt-nix.lib. instead?

Describe alternatives you've considered see above

Additional context