fix(ai): always include reasoning.encrypted_content for codex (#484)

packages/ai/test/openai-codex-include.test.ts

@@ -0,0 +1,27 @@
+import { describe, expect, it } from "vitest";
+import { type RequestBody, transformRequestBody } from "../src/providers/openai-codex/request-transformer.js";
+
+describe("openai-codex include handling", () => {
+	it("always includes reasoning.encrypted_content when caller include is custom", async () => {
+		const body: RequestBody = {
+			model: "gpt-5.1-codex",
+		};
+
+		const transformed = await transformRequestBody(body, "CODEX_INSTRUCTIONS", { include: ["foo"] }, true);
+		expect(transformed.include).toEqual(["foo", "reasoning.encrypted_content"]);
+	});
+
+	it("does not duplicate reasoning.encrypted_content", async () => {
+		const body: RequestBody = {
+			model: "gpt-5.1-codex",
+		};
+
+		const transformed = await transformRequestBody(
+			body,
+			"CODEX_INSTRUCTIONS",
+			{ include: ["foo", "reasoning.encrypted_content"] },
+			true,
+		);
+		expect(transformed.include).toEqual(["foo", "reasoning.encrypted_content"]);
+	});
+});