fix to have stash plugins work

modules/servers/stash.nix

@@ -1,7 +1,30 @@
-{ lib, config, ... }:
+{
+  lib,
+  config,
+  pkgs,
+  ...
+}:
 let
   cfg = config.my.servers.stash;
   setup = import ../factories/mkserver.nix { inherit lib config; };
+  stashPythonFHS = pkgs.buildFHSEnv {
+    name = "stash-python-fhs";
+    targetPkgs =
+      pkgs:
+      builtins.attrValues {
+        inherit (pkgs)
+          python3
+          gcc
+          glibc
+          ;
+        inherit (pkgs.python3Packages)
+          pip
+          virtualenv
+          ;
+        inherit (pkgs.stdenv.cc.cc) lib;
+      };
+    runScript = "bash";
+  };
 in
 {
   options.my.servers.stash = setup.mkOptions "stash" "xxx" 9999;
@@ -29,5 +52,13 @@ in
         ];
       };
     };
+    systemd.services.stash.environment = {
+      PYTHONPATH = "/var/lib/stash/venv/lib/python3.12/site-packages";
+      LD_LIBRARY_PATH = "${pkgs.stdenv.cc.cc.lib}/lib:${pkgs.glibc}/lib:${pkgs.zlib}/lib:${pkgs.libffi}/lib:${pkgs.openssl}/lib";
+    };
+    users.users.stash = {
+      isSystemUser = true;
+      packages = [ stashPythonFHS ];
+    };
   };
 }