improvement: simplify email design, refactor link/button to re-usable components and improve design

backend/src/services/smtp/emails/BaseButton.tsx

@@ -0,0 +1,17 @@
+import { Button } from "@react-email/components";
+
+type Props = {
+  href: string;
+  children: string;
+};
+
+export const BaseButton = ({ href, children }: Props) => {
+  return (
+    <Button
+      href={href}
+      className="rounded-[8px] py-[12px] px-[28px] my-[8px] text-center text-[16px] bg-[#EBF852] border-solid border border-[#d1e309] text-black font-medium"
+    >
+      {children}
+    </Button>
+  );
+};