feat(graphql): wire up model registration in schema emitter

Author: FionaBronwen

packages/graphql/src/schema-emitter.ts

@@ -1,6 +1,7 @@
 import {
   createDiagnosticCollector,
   navigateTypesInNamespace,
+  UsageFlags,
   type Diagnostic,
   type DiagnosticCollector,
   type EmitContext,
@@ -57,13 +58,14 @@ class GraphQLSchemaEmitter {
         this.registry.addEnum(node);
       },
       model: (node: Model) => {
-        // Add logic to handle the model node
+        // TODO: Determine usageFlag from mutation engine or usage tracking
+        this.registry.addModel(node, UsageFlags.Output);
       },
       exitEnum: (node: Enum) => {
         this.registry.materializeEnum(node.name);
       },
       exitModel: (node: Model) => {
-        // Add logic to handle the exit of the model node
+        this.registry.materializeModel(node.name);
       },
     };
   }

packages/graphql/test/emitter.test.ts

@@ -2,9 +2,19 @@ import { strictEqual } from "node:assert";
 import { describe, it } from "vitest";
 import { emitSingleSchema } from "./test-host.js";
 
-// For now, the expected output is a placeholder string.
-// In the future, this should be replaced with the actual GraphQL schema output.
-const expectedGraphQLSchema = `type Query {
+const expectedGraphQLSchema = `type Book {
+  name: String
+  page_count: String
+  published: String
+  price: String
+}
+
+type Author {
+  name: String
+  books: String
+}
+
+type Query {
   """
   A placeholder field. If you are seeing this, it means no operations were defined that could be emitted.
   """