fix(event handling): use internal pubsub for view update (#1118)

* start sub

* start implement subsciptions

* start subscription

* implementation for member done

* admin done

* fix: tests

* extend handlers

* prepary notification

* no errors in adminapi

* changed current sequence in all packages

* ignore mocks

* works

* subscriptions as singleton

* tests

* refactor: rename function scope var

internal/eventstore/models/aggregate.go

@@ -27,6 +27,10 @@ type Aggregate struct {
 	Precondition  *precondition
 }
 
+func (a *Aggregate) Type() AggregateType {
+	return a.typ
+}
+
 type precondition struct {
 	Query      *SearchQuery
 	Validation func(...*Event) error