feat: add basic website

Signed-off-by: kjuulh <contact@kjuulh.io>

templates/pages/error.html.jinja

@@ -0,0 +1,10 @@
+{% extends "base.html.jinja" %}
+
+{% block content %}
+<section class="max-w-lg mx-auto px-4 pt-24 text-center">
+    <p class="text-6xl font-bold text-gray-300">{{ status }}</p>
+    <h1 class="mt-4 text-2xl font-bold">{{ heading }}</h1>
+    <p class="mt-2 text-gray-600">{{ message }}</p>
+    <a href="/" class="inline-block mt-8 text-sm text-gray-500 hover:text-gray-700">&larr; Back to home</a>
+</section>
+{% endblock %}