feat: impl catch-all for parked domains

servers/keymaker/docker-compose.d/custom/nginx/conf.d/catch-all.conf

@@ -0,0 +1,11 @@
+server {
+    listen 80;
+    server_name _;
+
+    # SSL is managed by certbot, no need for a ssl listen; it will be generated automagically!
+
+    # default html page
+    location / {
+        proxy_pass http://pdsite;
+    }
+}