WIP: working on correct connect and disconnect

- introduced new types to encapsulate behaviour: RagConnectTokenMap, RagConnectPublisher
- move lastValue (of sendDefinitions) into new publisher
- create connectToken outside of handlers
- MqttHandler: make wildcardPatterns a list
- RestHandler: update dependency requirement to Spark 3.9.3 in order to unmap existing routes upon disconnect
- testing disconnect functionality in (most) existing tests
- still sometimes (!) getting "Top of handler stack does not match at pop!" Error during connect