Improves the invite mechanism for remote clusters (#31025)

Co-authored-by: Miguel de la Cruz <miguel@ctrlz.es>

server/public/model/remote_cluster.go

@@ -363,10 +363,12 @@ type RemoteClusterPing struct {
 
 // RemoteClusterInvite represents an invitation to establish a simple trust with a remote cluster.
 type RemoteClusterInvite struct {
-	RemoteId     string `json:"remote_id"`
-	RemoteTeamId string `json:"remote_team_id"` // Deprecated: this field is no longer used. It's only kept for backwards compatibility.
-	SiteURL      string `json:"site_url"`
-	Token        string `json:"token"`
+	RemoteId       string `json:"remote_id"`
+	RemoteTeamId   string `json:"remote_team_id"` // Deprecated: this field is no longer used. It's only kept for backwards compatibility.
+	SiteURL        string `json:"site_url"`
+	Token          string `json:"token"`
+	RefreshedToken string `json:"refreshed_token,omitempty"` // New token generated by the remote cluster when accepting an invitation
+	Version        int    `json:"version,omitempty"`
 }
 
 func (rci *RemoteClusterInvite) IsValid() *AppError {

server/public/model/remote_cluster_test.go

@@ -160,9 +160,11 @@ func TestRemoteClusterInviteEncryption(t *testing.T) {
 
 func makeInvite(url string) RemoteClusterInvite {
 	return RemoteClusterInvite{
-		RemoteId: NewId(),
-		SiteURL:  url,
-		Token:    NewId(),
+		RemoteId:       NewId(),
+		SiteURL:        url,
+		Token:          NewId(),
+		RefreshedToken: NewId(),
+		Version:        2,
 	}
 }