fix(ui): ensure terminal takes full viewport height on all devices (freeCodeCamp#61423)

Author: tanmaygautam11

client/src/templates/Challenges/classic/xterm.css

@@ -0,0 +1,3 @@
+.xterm-screen {
+  height: 100vh !important;
+}

client/src/templates/Challenges/classic/xterm.tsx

@@ -4,6 +4,7 @@ import type { FitAddon } from 'xterm-addon-fit';
 import { useTranslation } from 'react-i18next';
 
 import { registerTerminal } from '../utils/python-worker-handler';
+import './xterm.css';
 
 const registerServiceWorker = async () => {
   if ('serviceWorker' in navigator) {
@@ -35,6 +36,7 @@ export const XtermTerminal = ({
       const disposables: IDisposable[] = [];
       const { Terminal } = await import('xterm');
       const { FitAddon } = await import('xterm-addon-fit');
+
       // Setting convertEol so that \n is converted to \r\n. Otherwise the terminal
       // will interpret \n as line feed and just move the cursor to the next line.
       // convertEol makes every \n a \r\n.