chore(frontend): changed source code to src folder from root

frontend/src/pages/404.tsx

@@ -0,0 +1,39 @@
+import Head from 'next/head';
+import Image from 'next/image';
+import Link from 'next/link';
+
+export default function Custom404() {
+  return (
+    <div className='bg-bunker-800 md:h-screen flex flex-col justify-between'>
+      <Head>
+        <title>Infisical | Page Not Found</title>
+        <link rel='icon' href='/infisical.ico' />
+      </Head>
+      <div className='flex flex-col items-center justify-center text-gray-200 h-screen w-screen'>
+        <p className='text-4xl mt-32'>Oops, something went wrong</p>
+        <p className='mt-2 mb-1 text-lg'>
+          Think this is a mistake? Email{' '}
+          <a
+            className='text-primary underline underline-offset-4'
+            href='mailto:[email protected]'
+          >
+            team@infisical.com
+          </a>{' '}
+          and we`ll fix it!{' '}
+        </p>
+        <Link
+          href='/dashboard'
+          className='bg-mineshaft-500 mt-8 py-2 px-4 rounded-md hover:bg-primary diration-200 hover:text-black cursor-pointer font-semibold'
+        >
+          Go to Dashboard
+        </Link>
+        <Image
+          src='/images/dragon-404.svg'
+          height={554}
+          width={942}
+          alt='infisical dragon - page not found'
+        ></Image>
+      </div>
+    </div>
+  );
+}