added routes for rss, sitemap, updated footer

frontend/routes/rss/index.tsx

@@ -0,0 +1,3 @@
+export function handler(req: Request): Response {
+  return Response.redirect(`${Deno.env.get("RSS_URI")}`, 307);
+}

frontend/routes/sitemap/index.tsx

@@ -0,0 +1,3 @@
+export function handler(req: Request): Response {
+  return Response.redirect(`${Deno.env.get("SITEMAP_URI")}`, 307);
+}