FIX: Remove splash screen in no-js view (#17223)

We use javascript to remove the splash screen when the site boots up. If the user has js disabled, they get stuck on the splash screen.

If the user has js disabled. We don't show the splash screen at all.

app/views/common/_discourse_splash.html.erb

@@ -3,7 +3,7 @@
   <style>
     html {
       background: var(--secondary);
-      overflow: hidden !important;
+      overflow-y: hidden !important;
     }
 
     #d-splash {
@@ -29,6 +29,7 @@
       animation: fade-in 0.5s ease-in-out;
       animation-delay: 2.5s;
       animation-fill-mode: forwards;
+      color: var(--primary);
     }
 
     #d-splash .preloader-text:after {
@@ -79,5 +80,17 @@
   <div class="preloader-text">
     <span> <%= I18n.t("js.preloader_text") %> </span>
   </div>
+
+  <noscript>
+    <style>
+      html {
+        overflow-y: initial !important;
+      }
+
+      #d-splash {
+        display: none;
+      }
+    </style>
+  </noscript>
 </section>
 <%- end %>