fix: standardize filename to kebab-case 🐍➡️🥙 (#302)

Probably not the most exciting PR you’ll get today, but I noticed that
every file in the repo follows kebab-case… except one brave little
underscore in `cli_singlepass.tsx`.

So I made the world a little more consistent. Just a filename rename —
no logic changes, no semicolons harmed

Didn’t touch any code, I promise. Just bringing order to the filesystem
— one hyphen at a time.

codex-cli/src/cli.tsx

@@ -12,7 +12,7 @@ import type { AppConfig } from "./utils/config";
 import type { ResponseItem } from "openai/resources/responses/responses";
 
 import App from "./app";
-import { runSinglePass } from "./cli_singlepass";
+import { runSinglePass } from "./cli-singlepass";
 import { AgentLoop } from "./utils/agent/agent-loop";
 import { initLogger } from "./utils/agent/log";
 import { ReviewDecision } from "./utils/agent/review";