hippocampus: backups: clear old gitea backups

machines/hippocampus/backups/gitea.nix

@@ -1,6 +1,24 @@
-{ ... }: {
+{ pkgs, config, ... }: {
   services.gitea.dump = {
     enable = true;
     interval = "2:45";
   };
+  systemd.timers."gitea-clear-dump" = {
+    wantedBy = [ "timers.target" ];
+    timerConfig = {
+      OnCalendar = "daily";
+      Persistent = true;
+      Unit = "gitea-clear-dump.service";
+    };
+  };
+
+  systemd.services."gitea-clear-dump" = {
+    script = ''
+      ${pkgs.findutils}/bin/find /var/lib/gitea/dump -type f -ctime +5 -exec rm -f {} \;
+    '';
+    serviceConfig = {
+      Type = "oneshot";
+      User = config.services.gitea.user;
+    };
+  };
 }