* Stores a cache of inactive connections so their subscriptions are recovered on reconnections
* Adds test for getUserIDsForWorkspace and simplify messages through helpers
* Make the plugin websocket client more resilient
* Remove missed event callback and limit ws state polling to one at a time
* Add read lock for the plugin adapter and guarantee atomic ops on inactiveAt
* Add mutex to the plugin adapter client and tests to cover for races
* Split plugin adapter mutex in two and use them to lock only on data access
* Group plugin adapter fields by the mutex that's guarding them
