fix: avoid reference unused enums in generated policy code

Author: ymc9

tests/regression/tests/issue-1835.test.ts

@@ -0,0 +1,28 @@
+import { loadSchema } from '@zenstackhq/testtools';
+
+describe('issue 1835', () => {
+    it('regression', async () => {
+        await loadSchema(
+            `
+        enum Enum {
+            SOME_VALUE
+            ANOTHER_VALUE
+        }
+
+        model Model {
+            id String @id @default(cuid())
+            value Enum
+            @@ignore
+        }
+
+        model AnotherModel {
+            id String @id @default(cuid())
+        }
+            `,
+            {
+                provider: 'postgresql',
+                pushDb: false,
+            }
+        );
+    });
+});