refactor(notification): use new queue package (#9360)

# Which Problems Are Solved

The recently introduced notification queue have potential race conditions.

# How the Problems Are Solved

Current code is refactored to use the queue package, which is safe in
regards of concurrency.

# Additional Changes

- the queue is included in startup
- improved code quality of queue

# Additional Context

- closes https://github.com/zitadel/zitadel/issues/9278

cmd/setup/river_queue_repeatable.go

@@ -16,7 +16,7 @@ func (mig *RiverMigrateRepeatable) Execute(ctx context.Context, _ eventstore.Eve
 	if mig.client.Type() != "postgres" {
 		return nil
 	}
-	return queue.New(mig.client).ExecuteMigrations(ctx)
+	return queue.NewMigrator(mig.client).Execute(ctx)
 }
 
 func (mig *RiverMigrateRepeatable) String() string {

cmd/setup/setup.go

@@ -37,6 +37,7 @@ import (
 	notify_handler "github.com/zitadel/zitadel/internal/notification"
 	"github.com/zitadel/zitadel/internal/query"
 	"github.com/zitadel/zitadel/internal/query/projection"
+	"github.com/zitadel/zitadel/internal/queue"
 	es_v4 "github.com/zitadel/zitadel/internal/v2/eventstore"
 	es_v4_pg "github.com/zitadel/zitadel/internal/v2/eventstore/postgres"
 	"github.com/zitadel/zitadel/internal/webauthn"
@@ -466,6 +467,10 @@ func startCommandsQueries(
 		config.DefaultInstance.SecretGenerators,
 	)
 	logging.OnError(err).Fatal("unable to start commands")
+	q, err := queue.NewQueue(&queue.Config{
+		Client: dbClient,
+	})
+	logging.OnError(err).Fatal("unable to start queue")
 
 	notify_handler.Register(
 		ctx,
@@ -489,6 +494,7 @@ func startCommandsQueries(
 		keys.OIDC,
 		config.OIDC.DefaultBackChannelLogoutLifetime,
 		dbClient,
+		q,
 	)
 
 	return commands, queries, adminView, authView