Improve error messages

This improves error messages throughout. It might sometimes be too verbose, but that's better than being opaque (#74).

Also upgrades Deno's patch version.

Fixes #74

docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   website:
-    image: ghcr.io/bewcloud/bewcloud:v2.2.0
+    image: ghcr.io/bewcloud/bewcloud:v2.2.2
     restart: always
     ports:
       - 127.0.0.1:8000:8000