feat(compiler): run error section on ssr api call failure

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

packages/compiler/test/api-block-ssr.test.ts

@@ -32,3 +32,31 @@ test("a legacy ssr block is unchanged", () => {
 
   expect(generated).toContain("users.length");
 });
+
+test("an ssr block with an error section emits the error body and binds status/message/data", () => {
+  const generated = serverModule(`    api ssrUsers GET /api/users {
+      response {
+        return data.users.length
+      }
+      error {
+        return message + status + data
+      }
+    }`);
+
+  expect(generated).toContain('"errorBody"');
+  expect(generated).toContain("return message + status + data");
+  expect(generated).toContain("const status = $status");
+  expect(generated).toContain("const message = $message");
+  expect(generated).toContain("const data = $data");
+  expect(generated).toContain("__wrnexusEvalError");
+});
+
+test("an ssr block without an error section emits no catch entry for that binding", () => {
+  const generated = serverModule(`    api ssrUsers GET /api/users {
+      response {
+        return data.users.length
+      }
+    }`);
+
+  expect(generated).not.toContain('"errorBody"');
+});