[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/feature_flags.go

@@ -35,6 +35,9 @@ type FeatureFlags struct {
 
 	// Control support for custom data retention policies
 	CustomDataRetentionEnabled bool
+
+	// Enable timed dnd support for user status
+	TimedDND bool
 }
 
 func (f *FeatureFlags) SetDefaults() {
@@ -49,6 +52,7 @@ func (f *FeatureFlags) SetDefaults() {
 	f.PluginApps = ""
 	f.PluginFocalboard = ""
 	f.CustomDataRetentionEnabled = false
+	f.TimedDND = false
 }
 
 func (f *FeatureFlags) Plugins() map[string]string {