Greatly simplified start-up!

🚨 Breaking

• Removed StreamDeckClient; replaced with IStreamDeckConnection.
• Updated StreamDeckAction.StreamDeck to be IStreamDeckConnection.

⭐ Added

• Greatly simplfied starting a plug-in.
  • StreamDeckPlugin.Run()
  • StreamDeckPlugin.RunAsync()
• Added basic unit tests.
• Added GitHub workflows.
• Added StreamDeckAction.OnInit virtual.

♻ Changed

• Actions with StreamDeckAttribute are automatically registered.
• Complete re-write of action caching.
• Complete re-write of event routing.

🐞 Fixed

• Fixed an issue with incorrect actions being invoked.