Add scalar link__Import and enum link__Purpose to @link definition

src/Federation/Directives/LinkDirective.php

@@ -22,6 +22,36 @@ public static function definition(): string
 https://www.apollographql.com/docs/federation/federated-types/federated-directives#the-link-directive
 """
 directive @link(url: String!, as: String, for: link__Purpose, import: [link__Import]) repeatable on SCHEMA
+
+"""
+An element to import into the document.
+
+```graphql
+@link(url: "https://specs.apollo.dev/link/v1.0", import: ["@link", "Purpose"])
+```
+
+or an object with name and (optionally as):
+
+```graphql
+@link(url: "https://specs.apollo.dev/link/v1.0", import: [{ name: "Purpose", as: "LinkPurpose" }])
+```
+"""
+scalar link__Import
+
+"""
+The role of a @linked schema.
+"""
+enum link__Purpose {
+    """
+    Provide metadata necessary to securely resolve fields.
+    """
+    SECURITY
+
+    """
+    Provide metadata necessary to correctly resolve fields.
+    """
+    EXECUTION
+}
 GRAPHQL;
     }
 }