refactor: split configurations for fail2ban, postgres, and qbittorent into folders

modules/nixos-modules/server/fail2ban/impermanence.nix

@@ -0,0 +1,27 @@
+{
+  lib,
+  config,
+  ...
+}: let
+  dataFolder = "/var/lib/fail2ban";
+  dataFile = "fail2ban.sqlite3";
+in {
+  config = lib.mkIf (config.services.fail2ban.enable && config.host.impermanence.enable) {
+    assertions = [
+      {
+        assertion = config.services.fail2ban.daemonSettings.Definition.dbfile == "${dataFolder}/${dataFile}";
+        message = "fail2ban data file does not match persistence";
+      }
+    ];
+
+    environment.persistence."/persist/system/root" = {
+      directories = [
+        {
+          directory = dataFolder;
+          user = "fail2ban";
+          group = "fail2ban";
+        }
+      ];
+    };
+  };
+}