Show a nicer error message when server is installing

resources/scripts/components/screens/ServerInstalling.tsx

@@ -0,0 +1,16 @@
+import React from 'react';
+import PageContentBlock from '@/components/elements/PageContentBlock';
+
+export default () => (
+    <PageContentBlock>
+        <div className={'flex justify-center'}>
+            <div className={'w-full sm:w-3/4 md:w-1/2 p-12 md:p-20 bg-neutral-100 rounded-lg shadow-lg text-center'}>
+                <img src={'/assets/svgs/server_installing.svg'} className={'w-2/3 h-auto select-none'}/>
+                <h2 className={'mt-6 text-neutral-900 font-bold'}>Your server is installing.</h2>
+                <p className={'text-sm text-neutral-700 mt-2'}>
+                    Please check back in a few minutes.
+                </p>
+            </div>
+        </div>
+    </PageContentBlock>
+);