MM-16499: Adds ability to retrieve channels with total count f… (#11375)

* MM-16499: Adds ability to retrieve channels with total count for pagination.

* MM-16499: Switches to custom package name for squirrel.

model/channel.go

@@ -60,6 +60,11 @@ type ChannelWithTeamData struct {
 	TeamUpdateAt    int64  `json:"team_update_at"`
 }
 
+type ChannelsWithCount struct {
+	Channels   *ChannelListWithTeamData `json:"channels"`
+	TotalCount int64                    `json:"total_count"`
+}
+
 type ChannelPatch struct {
 	DisplayName      *string `json:"display_name"`
 	Name             *string `json:"name"`
@@ -111,6 +116,17 @@ func (o *ChannelPatch) ToJson() string {
 	return string(b)
 }
 
+func (o *ChannelsWithCount) ToJson() []byte {
+	b, _ := json.Marshal(o)
+	return b
+}
+
+func ChannelsWithCountFromJson(data io.Reader) *ChannelsWithCount {
+	var o *ChannelsWithCount
+	json.NewDecoder(data).Decode(&o)
+	return o
+}
+
 func ChannelFromJson(data io.Reader) *Channel {
 	var o *Channel
 	json.NewDecoder(data).Decode(&o)