Accept both text_completion and chat.completion in completions response

The OpenRouter API returns object: "chat.completion" for the /completions
endpoint, but the SDK was only accepting "text_completion". This caused
validation errors when using the completions.generate() method.

This change updates the CompletionResponse type and Zod schema to accept
either value, since the API behavior may vary or change.

Also added an E2E test to verify completions work correctly.

Fixes #101

Author: bledden

.speakeasy/in.openapi.yaml

@@ -6189,7 +6189,9 @@ components:
           type: string
         object:
           type: string
-          const: text_completion
+          enum:
+            - text_completion
+            - chat.completion
         created:
           type: number
         model:

src/models/completionresponse.ts

@@ -19,7 +19,7 @@ import { SDKValidationError } from "./errors/sdkvalidationerror.js";
 
 export type CompletionResponse = {
   id: string;
-  object: "text_completion";
+  object: "text_completion" | "chat.completion";
   created: number;
   model: string;
   provider?: string | undefined;
@@ -34,7 +34,7 @@ export const CompletionResponse$inboundSchema: z.ZodType<
   unknown
 > = z.object({
   id: z.string(),
-  object: z.literal("text_completion"),
+  object: z.enum(["text_completion", "chat.completion"]),
   created: z.number(),
   model: z.string(),
   provider: z.string().optional(),

tests/e2e/completions.test.ts

@@ -0,0 +1,35 @@
+import { beforeAll, describe, expect, it } from 'vitest';
+import { OpenRouter } from '../../src/sdk/sdk.js';
+
+describe('Completions E2E Tests', () => {
+  let client: OpenRouter;
+
+  beforeAll(() => {
+    const apiKey = process.env.OPENROUTER_API_KEY;
+    if (!apiKey) {
+      throw new Error('OPENROUTER_API_KEY environment variable is required for e2e tests');
+    }
+
+    client = new OpenRouter({
+      apiKey,
+    });
+  });
+
+  describe('completions.generate()', () => {
+    it('should successfully generate a text completion', async () => {
+      const response = await client.completions.generate({
+        model: 'meta-llama/llama-3.2-1b-instruct',
+        prompt: '5 + 7 = ',
+        maxTokens: 10,
+        stream: false,
+      });
+
+      expect(response).toBeDefined();
+      expect(response.id).toBeDefined();
+      // API returns chat.completion, SDK should accept both
+      expect(['text_completion', 'chat.completion']).toContain(response.object);
+      expect(Array.isArray(response.choices)).toBe(true);
+      expect(response.choices.length).toBeGreaterThan(0);
+    }, 30000);
+  });
+});