Add Event Bus (#184)

Major internal refactor to use an event bus to pass event/messages along. These changes are largely invisible user facing but sets up internal design for real time stats and information.

- `--watch-config` logic refactored for events
- remove multiple SSE api endpoints, replaced with /api/events
- keep all functionality essentially the same
- UI/backend sync is in near real time now

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/tidwall/gjson v1.18.0
 	github.com/tidwall/sjson v1.2.5
 	gopkg.in/yaml.v3 v3.0.1
+	github.com/kelindar/event v1.5.2
 )
 
 require (