feat(user-management): add DirectoryManaged to OrganizationMembership (#508)

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: wzahedi

pkg/usermanagement/client.go

@@ -137,6 +137,9 @@ type OrganizationMembership struct {
 	// The Status of the Organization.
 	Status OrganizationMembershipStatus `json:"status"`
 
+	// Whether the membership is managed by a directory sync connection.
+	DirectoryManaged bool `json:"directory_managed"`
+
 	// CustomAttributes contains custom attributes from the IdP
 	CustomAttributes map[string]interface{} `json:"custom_attributes"`