caddy config update and docs update

README.md

···
 // conf/Caddyfile
 
 yourdomain.com {
-    reverse_proxy relay:2470
+    tls {
+      on_demand
+    }
+
+    handle /xrpc/com.atproto.sync.subscribeRepos {
+      reverse_proxy 127.0.0.1:2470 {
+        header_up Origin "yourdomain.com"
+      }
+    }
+
+    reverse_proxy localhost:2470
 }
 ```
 
···
 we can then use `goat` to add hosts to the relay
 
 ```bash
-shuf hosts.txt | parallel goat relay admin host add {}
+shuf hosts.txt | RELAY_HOST=http://localhost:2470 parallel goat relay admin host add {}
 ```

conf/Caddyfile

···
       on_demand
     }
 
+    handle /xrpc/com.atproto.sync.subscribeRepos {
+      reverse_proxy 127.0.0.1:2470 {
+        header_up Origin "yourdomain.com"
+      }
+    }
+
     reverse_proxy localhost:2470
 }