[MM-8497] Ability to set Do Not Disturb for a specified period of time (#17680)

* Revert "Revert "[MM-8497] Ability to set Do Not Disturb for a specified period of time (#16067)" (#17657)"

This reverts commit ff383990f8.

* add debug log for recurring function

* add feature flag for dnd timed status

* refactoring changes

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

model/status.go

@@ -25,6 +25,8 @@ type Status struct {
 	Manual         bool   `json:"manual"`
 	LastActivityAt int64  `json:"last_activity_at"`
 	ActiveChannel  string `json:"active_channel,omitempty" db:"-"`
+	DNDEndTime     int64  `json:"dnd_end_time"`
+	PrevStatus     string `json:"-"`
 }
 
 func (o *Status) ToJson() string {