open-webui-oci: replace version with image option

tests/run/open-webui-oci.nix

@@ -0,0 +1,37 @@
+let
+  port = 3000;
+in
+{
+  name = "open-webui-oci-test";
+
+  nodes.machine =
+    { ... }:
+    {
+      imports = [
+        ../../modules/nixos/open-webui-oci
+      ];
+
+      config = {
+        virtualisation.diskSize = 32768;
+        virtualisation.memorySize = 8192;
+
+        services.open-webui-oci = {
+          enable = true;
+          inherit port;
+        };
+
+        networking.firewall.enable = false;
+      };
+    };
+
+  testScript = ''
+    start_all()
+
+    machine.wait_for_unit("default.target")
+
+    machine.wait_for_unit("podman-open-webui.service")
+    machine.wait_for_open_port(${toString port})
+
+    machine.succeed("curl --fail --retry 10 --retry-delay 5 --retry-connrefused http://localhost:${toString port}/")
+  '';
+}