[MM-24828] Take into account group synced state of team and channel when sending notifications (#14477)

* MM-24828 Take into account group synced state of team and channel when getting groups for mentions

* Update app/notification_test.go

* i18n-extract

* Revert "i18n-extract"

This reverts commit dcb0426b98afa4646c26870c0e3a1236f99fda17.

* Trigger CI

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

app/notification.go

@@ -40,13 +40,7 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	if a.allowGroupMentions(post) {
 		gchan = make(chan store.StoreResult, 1)
 		go func() {
-			groups, err := a.Srv().Store.Group().GetGroups(0, 0, model.GroupSearchOpts{FilterAllowReference: true})
-			groupsMap := make(map[string]*model.Group)
-			if err == nil {
-				for _, group := range groups {
-					groupsMap[group.Name] = group
-				}
-			}
+			groupsMap, err := a.getGroupsAllowedForReferenceInChannel(channel, team)
 			gchan <- store.StoreResult{Data: groupsMap, Err: err}
 			close(gchan)
 		}()
@@ -755,6 +749,39 @@ func (a *App) allowGroupMentions(post *model.Post) bool {
 	return true
 }
 
+// getGroupsAllowedForReferenceInChannel returns a map of groups allowed for reference in a given channel and team.
+func (a *App) getGroupsAllowedForReferenceInChannel(channel *model.Channel, team *model.Team) (map[string]*model.Group, *model.AppError) {
+	var err *model.AppError
+	groupsMap := make(map[string]*model.Group)
+	opts := model.GroupSearchOpts{FilterAllowReference: true}
+
+	if channel.IsGroupConstrained() || team.IsGroupConstrained() {
+		var groups []*model.GroupWithSchemeAdmin
+		if channel.IsGroupConstrained() {
+			groups, err = a.Srv().Store.Group().GetGroupsByChannel(channel.Id, opts)
+		} else {
+			groups, err = a.Srv().Store.Group().GetGroupsByTeam(team.Id, opts)
+		}
+		if err != nil {
+			return nil, err
+		}
+		for _, group := range groups {
+			groupsMap[group.Group.Name] = &group.Group
+		}
+		return groupsMap, nil
+	}
+
+	groups, err := a.Srv().Store.Group().GetGroups(0, 0, opts)
+	if err != nil {
+		return nil, err
+	}
+	for _, group := range groups {
+		groupsMap[group.Name] = group
+	}
+
+	return groupsMap, nil
+}
+
 // Given a map of user IDs to profiles, returns a list of mention
 // keywords for all users in the channel.
 func (a *App) getMentionKeywordsInChannel(profiles map[string]*model.User, allowChannelMentions bool, channelMemberNotifyPropsMap map[string]model.StringMap) map[string][]string {