fix: make RegisterCritical variadic for API consistency with RegisterCriticalUntilLatest

mc/event/event_bus.go

@@ -139,10 +139,12 @@ func (l *Loop) RegisterLow(eventType reflect.Type, hv reflect.Value, critical bo
 
 // RegisterCritical registers a handler that will close the loop if it returns an error.
 // Warning: If a bad handler is passed in the program will panic.
-func (l *Loop) RegisterCritical(h any) {
+func (l *Loop) RegisterCritical(hs ...any) {
+	for _, h := range hs {
 		eventType, hv := ValidateHandler(h)
 		l.HandlerFunctions[eventType] = append(l.HandlerFunctions[eventType], hv)
 	}
+}
 
 // FireFound triggers all handlers registered for the specified event type and returns if handlers were found or an error occurred.
 func (l *Loop) FireFound(event any) (found bool, err error) {