Multiple fix

[sproctor]

The protection against multiple concurrent usages was broken to never allow restarting. This change is pretty significant, but also simple. LighthouseState is no longer a member variable, instead a new state is created on each call to LighthouseClient.discoverDevices(). shouldPersist is no longer possible to implement. If that feature is required, an existing list could be passed to discoverDevices.

I removed DiscoveryManager. It didn't actually manage anything anymore. The two helper functions from there made more sense as part of RealLighthouseClient.

Fixes #31

[sproctor]

One last thing to note, discoverDevices now runs on the current coroutine context and the proper context should be set by the consumer.

[ivanempire]

Two quick notes:

1. Is the idea to have .flowOn() at the consumer level? EDIT: I think part of the reason I added it there was to make sure IO is used and to make it possible to add one during testing....which I totally wrote since xD
2. Won't the removal of the mutex cause an issue where the second call to discoverDevices() throws an error up the Flow?

[ivanempire]

Closing for now since we're both async on this work - feel free to reopen :)

[sproctor]

1. Deciding which dispatcher to use should be left to the user.

2. A new LighthouseState is created on each discoverDevices() call, so it avoids the issues with re-use. I don't remember if I tried concurrent searches. If you're interested in this work I can test it and make any relevant fixes.

You don't seem keen on merging my stuff, so unless you tell me otherwise, I'll just leave stuff on my own branch. It'll save me the work of trying to make things mostly mergeable (although, I did make a lot of my merges dependent on previous ones because I didn't have the time to break them up completely).

[ivanempire]

Nah I'm cool with it, I just want smaller commits/also been taking a break. You're all good, I just also don't have the best environment for testing on desktop - I swear I'll get to it xD