Default system if theme unrecognized (#440)

Author: J-T-McC

resources/views/components/theme-switcher.blade.php

@@ -1,6 +1,6 @@
 <script>
 setDarkClass = () => {
-    if (localStorage.theme === 'dark' || (!('theme' in localStorage) && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
+    if (localStorage.theme === 'dark' || ((!('theme' in localStorage) || !['light', 'dark'].includes(localStorage.theme)) && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
         document.documentElement.classList.add('dark')
     } else {
         document.documentElement.classList.remove('dark')