re-enable Prettier check for codex-cli in CI (#417)

This check was lost in https://github.com/openai/codex/pull/287. Both
the root folder and `codex-cli/` have their own `pnpm format` commands
that check the formatting of different things.

Also ran `pnpm format:fix` to fix the formatting violations that got in
while this was disabled in CI.

---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/417).
* #420
* #419
* #416
* __->__ #417

codex-cli/tests/input-utils.test.ts

@@ -14,9 +14,13 @@ describe("createInputItem", () => {
 
   it("includes image content for existing file", async () => {
     const fakeBuffer = Buffer.from("fake image content");
-    const readSpy = vi.spyOn(fs, "readFile").mockResolvedValue(fakeBuffer as any);
+    const readSpy = vi
+      .spyOn(fs, "readFile")
+      .mockResolvedValue(fakeBuffer as any);
     const result = await createInputItem("hello", ["dummy-path"]);
-    const expectedUrl = `data:application/octet-stream;base64,${fakeBuffer.toString("base64")}`;
+    const expectedUrl = `data:application/octet-stream;base64,${fakeBuffer.toString(
+      "base64",
+    )}`;
     expect(result.role).toBe("user");
     expect(result.type).toBe("message");
     expect(result.content.length).toBe(2);
@@ -40,4 +44,4 @@ describe("createInputItem", () => {
       text: "[missing image: does-not-exist.png]",
     });
   });
-});
+});