update links to use env

src/lib/components/MobileNav.svelte

@@ -1,5 +1,6 @@
 <script lang="ts">
     import { afterNavigate } from '$app/navigation';
+    import { PUBLIC_APPWRITE_DASHBOARD } from '$env/static/public';
     import { IsLoggedIn } from '$lib/components';
     import { GITHUB_STARS } from '$lib/constants';
     import type { NavLink } from '$lib/layouts/Main.svelte';
@@ -17,7 +18,10 @@
 <nav class="web-side-nav web-is-not-desktop" class:u-hide={!open}>
     <div class="web-side-nav-wrapper web-u-padding-inline-16">
         <div class="u-flex items-center u-gap-8">
-            <a href="https://cloud.appwrite.io/register" class="web-button is-secondary web-u-flex-1">
+            <a
+                href={`${PUBLIC_APPWRITE_DASHBOARD}/register`}
+                class="web-button is-secondary web-u-flex-1"
+            >
                 Sign up
             </a>
             <IsLoggedIn classes="web-u-flex-1" />