Add metrics for mobile versions snapshots (#28191)

* Add metrics for mobile versions snapshots

* Add notifications disabled and fix lint

* Address feedback

* Verify all references to JobTypeActiveUsers

* Fix typos

* Improve platform values

* Add test and MySQL support

server/channels/jobs/mobile_session_metadata/scheduler.go

@@ -0,0 +1,20 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mobile_session_metadata
+
+import (
+	"time"
+
+	"github.com/mattermost/mattermost/server/public/model"
+	"github.com/mattermost/mattermost/server/v8/channels/jobs"
+)
+
+const schedFreq = 24 * time.Hour
+
+func MakeScheduler(jobServer *jobs.JobServer) *jobs.PeriodicScheduler {
+	isEnabled := func(cfg *model.Config) bool {
+		return *cfg.MetricsSettings.EnableClientMetrics
+	}
+	return jobs.NewPeriodicScheduler(jobServer, model.JobTypeMobileSessionMetadata, schedFreq, isEnabled)
+}