chore(vendor): import pi 0.85.1

Imported as a linear vendor commit so forge rebases do not replay the upstream root tree.

git-subtree-dir: third_party/pi

git-subtree-split: d981de1229ef899957bbe968bc8dcda02a21f477

third_party/pi/packages/ai/src/providers/openai-codex.ts

@@ -0,0 +1,22 @@
+import { openAICodexResponsesApi } from "../api/openai-codex-responses.lazy.ts";
+import { lazyOAuth } from "../auth/helpers.ts";
+import { loadOpenAICodexOAuth } from "../auth/oauth/load.ts";
+import { createProvider, type Provider } from "../models.ts";
+import { OPENAI_CODEX_MODELS } from "./openai-codex.models.ts";
+
+export function openaiCodexProvider(): Provider<"openai-codex-responses"> {
+	return createProvider({
+		id: "openai-codex",
+		name: "OpenAI Codex",
+		baseUrl: "https://chatgpt.com/backend-api",
+		auth: {
+			oauth: lazyOAuth({
+				name: "OpenAI (ChatGPT Plus/Pro)",
+				isSubscription: true,
+				load: loadOpenAICodexOAuth,
+			}),
+		},
+		models: Object.values(OPENAI_CODEX_MODELS),
+		api: openAICodexResponsesApi(),
+	});
+}