replace pre-commit with shell script

This saves one flake input and some python dependencies

flake-parts/devShells/default.nix

@@ -7,7 +7,6 @@
     }: {
       devShells.default = pkgs.mkShell {
         inputsFrom = [
-          config.pre-commit.devShell
           config.treefmt.build.devShell
         ];
         packages = [
@@ -15,6 +14,9 @@
           self'.packages.tea-create-pr
           self'.packages.merge-after-ci
         ];
+        shellHook = ''
+          ln -sf ../../scripts/pre-commit .git/hooks/pre-commit
+        '';
       };
     };
 }

flake-parts/formatting.nix

@@ -3,10 +3,9 @@
 , ...
 }: {
   imports = [
-    inputs.pre-commit-hooks-nix.flakeModule
     inputs.treefmt-nix.flakeModule
   ];
-  perSystem = { pkgs, config, ... }: {
+  perSystem = { pkgs, ... }: {
     treefmt.projectRootFile = "flake.nix";
     treefmt.flakeCheck = true;
     treefmt.flakeFormatter = true;
@@ -37,18 +36,5 @@
       ];
       includes = [ "*.py" ];
     };
-
-    # we already run treefmt in ci
-    pre-commit.check.enable = false;
-    # activated in devShells via inputsFrom = [config.pre-commit.devShell];
-    pre-commit.settings.hooks.format-all = {
-      name = "format-all";
-      enable = true;
-      pass_filenames = true;
-      entry = toString (pkgs.writeScript "treefmt" ''
-        #!${pkgs.bash}/bin/bash
-        ${config.treefmt.build.wrapper}/bin/treefmt --clear-cache --fail-on-change "$@"
-      '');
-    };
   };
 }