Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/boards/app/initialize.go

@@ -0,0 +1,29 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package app
+
+import (
+	"context"
+
+	"github.com/mattermost/mattermost-server/v6/server/platform/shared/mlog"
+)
+
+// initialize is called when the App is first created.
+func (a *App) initialize(skipTemplateInit bool) {
+	if !skipTemplateInit {
+		if err := a.InitTemplates(); err != nil {
+			a.logger.Error(`InitializeTemplates failed`, mlog.Err(err))
+		}
+	}
+}
+
+func (a *App) Shutdown() {
+	if a.blockChangeNotifier != nil {
+		ctx, cancel := context.WithTimeout(context.Background(), blockChangeNotifierShutdownTimeout)
+		defer cancel()
+		if !a.blockChangeNotifier.Shutdown(ctx) {
+			a.logger.Warn("blockChangeNotifier shutdown timed out")
+		}
+	}
+}