[MM-31497] - Prevent end users from inviting people and exceeding the free tier limits (#16786)

* [MM-31497] - Prevent end users from inviting people and exceeding the free tier limits

* Update error

* Commit forgotten code

* Chnage impl-1

* Change impl-2

* Remove test

* Include tier status

* Renable permissions check

* Change endpoint name

* Update endpoint

* Update api4/cloud.go

Co-authored-by: Maria A Nunez <maria.nunez@mattermost.com>

* Add test for new endpoint

* Format code

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
Co-authored-by: Maria A Nunez <maria.nunez@mattermost.com>

model/client4.go

@@ -5752,6 +5752,18 @@ func (c *Client4) GetSubscription() (*Subscription, *Response) {
 	return subscription, BuildResponse(r)
 }
 
+func (c *Client4) GetSubscriptionStats() (*SubscriptionStats, *Response) {
+	r, appErr := c.DoApiGet(c.GetCloudRoute()+"/subscription/stats", "")
+	if appErr != nil {
+		return nil, BuildErrorResponse(r, appErr)
+	}
+	defer closeBody(r)
+
+	var stats *SubscriptionStats
+	json.NewDecoder(r.Body).Decode(&stats)
+	return stats, BuildResponse(r)
+}
+
 func (c *Client4) GetInvoicesForSubscription() ([]*Invoice, *Response) {
 	r, appErr := c.DoApiGet(c.GetCloudRoute()+"/subscription/invoices", "")
 	if appErr != nil {

model/cloud.go

@@ -128,3 +128,8 @@ type FailedPayment struct {
 	LastFour       int    `json:"last_four"`
 	FailureMessage string `json:"failure_message"`
 }
+
+type SubscriptionStats struct {
+	RemainingSeats int    `json:"remaining_seats"`
+	IsPaidTier     string `json:"is_paid_tier"`
+}