Dynamic build and deployment on Vercel (#21)

* Make deployment doable on EUS and Vercel servers

* Revert to adapter-auto for now

* Remove `r/` layout file

* Fixing deployment configuration and landing page for redirects

* Clean up PR

src/routes/r/[shortname]/+page.server.js

@@ -18,5 +18,6 @@ export const load = async ({ params }) => {
 
     return {
         shortname: shortname,
+        availableShortnames: CMSresponse,
     }
 };

src/routes/r/[shortname]/+page.svelte

@@ -4,9 +4,18 @@
 </script>
 
 <Section>
-	<p class="page-title">Where am I?</p>
-	<p>
-        Oops! We don't have a page for <code>"r/{data.shortname}"</code>.
-	</p>
-	<p>Please try again!</p>
+	<p class="page-title">Can't redirect you to <code>"r/{data.shortname}"</code>!</p>
+	<hr class="border-2 w-1/2">
+	<div>
+		Maybe you were trying to get to:
+		<ul>
+			{#each data.availableShortnames as s}
+			<li class="list-disc list-inside">
+				<a href={s.url}>
+					/r/{s.shortname}
+				</a>
+			</li>
+			{/each}
+		</ul>
+	</div>
 </Section>