Add a couple of annotation errors

Longer descriptions than is common in this repo, but there isn't actually a
good reason for them to all be terse afaict

Author: SimonWoolf

protocol/errors.json

@@ -204,6 +204,9 @@
   "92006": "unable to perform operation without objectId or path",
   "92007": "operation not processable on path",
 
+  "93001": "attempt to add an annotation listener without having requested the annotation_subscribe channel mode in ChannelOptions, which won't do anything (we only deliver annotations to clients who have explicitly requested them)",
+  "93002": "Attempt to publish an annotation on a channel which isn't in a namespace which has Mutable Messages enabled",
+
   "101000": "must have a non-empty name for the space",
   "101001": "must enter a space to perform this operation",
   "101002": "lock request already exists",