prosodyctl check: Warn about invalid domain names in the config file
This ensures that domain names of virtual hosts and components are valid in
XMPP, and that they are encoded correctly.
# Tombstones
[Client] Romeo
jid: romeo@localhost
password: password
[Client] Juliet
jid: juliet-tombstones@localhost
password: password
---------
Romeo connects
Juliet connects
Juliet sends:
<iq type="set" id="bye">
<query xmlns="jabber:iq:register">
<remove/>
</query>
</iq>
# Scansion gets disconnected right after this with a stream error makes
# scansion itself abort, so we preemptively disconnect to avoid that
# Juliet receives:
# <iq type="result" id="bye"/>
Juliet disconnects
Romeo sends:
<presence type="probe" to="${Juliet's JID}"/>
Romeo receives:
<presence type="error" from="${Juliet's JID}"/>
Romeo receives:
<presence type="unsubscribed" from="${Juliet's JID}"/>