Category watch state (#7109)

* feat: wip, category watch change

* feat: pass data to client

* feat: allow changing state

* fix: account page categories

* fix: show in unread if topic is followed or category is watched

* feat: add default watch state to acp

* feat: save user category watch state

* feat: update unread recent pages

* fix: remove dupe code

* fix: flip conditions

* fix: handle empty arrays

* fix: ignore/watch on others profile

* feat: upgrade script for category states

if there are any users ignoring categories set their state in new zset and delete cid:<cid>:ignorers

* fix: upgrade

* fix: tests

* fix: redis count

* fix: more tests

src/database/postgres/sorted.js

@@ -348,7 +348,7 @@ SELECT z."score" s
 
 	module.sortedSetsScore = function (keys, value, callback) {
 		if (!Array.isArray(keys) || !keys.length) {
-			return callback();
+			return callback(null, []);
 		}
 
 		value = helpers.valueToString(value);