clarify which option is the default

default.yaml

@@ -144,7 +144,7 @@ server:
     # whether to look up user hostnames with reverse DNS. there are 3 possibilities:
     # 1. lookup-hostnames enabled, IP cloaking disabled; users will see each other's hostnames
     # 2. lookup-hostnames disabled, IP cloaking disabled; users will see each other's numeric IPs
-    # 3. IP cloaking enabled; users will see cloaked hostnames (see the ip-cloaking section)
+    # 3. [the default] IP cloaking enabled; users will see cloaked hostnames
     lookup-hostnames: false
     # whether to confirm hostname lookups using "forward-confirmed reverse DNS", i.e., for
     # any hostname returned from reverse DNS, resolve it back to an IP address and reject it