feat: improve config UI (#69)

* add first concept

* completed configuration ui update

* add button for testing email configuration

* improve mobile layout

* add migration

* run formatter

* delete unnecessary modal

* remove unused comment

frontend/src/components/admin/configuration/TestEmailButton.tsx

@@ -0,0 +1,27 @@
+import { Button } from "@mantine/core";
+import useUser from "../../../hooks/user.hook";
+import configService from "../../../services/config.service";
+import toast from "../../../utils/toast.util";
+
+const TestEmailButton = () => {
+  const { user } = useUser();
+
+  return (
+    <Button
+      variant="light"
+      onClick={() =>
+        configService
+          .sendTestEmail(user!.email)
+          .then(() => toast.success("Email sent successfully"))
+          .catch(() =>
+            toast.error(
+              "Failed to send the email. Please check the backend logs for more information."
+            )
+          )
+      }
+    >
+      Send test email
+    </Button>
+  );
+};
+export default TestEmailButton;