## What does this PR do?
* Implements the full `/clear` command in **codex‑cli**:
* Resets chat history **and** wipes the terminal screen.
* Shows a single system message: `Context cleared`.
* Adds comprehensive unit tests for the new behaviour.
## Why is it needed?
* Fixes user‑reported bugs:
* **#395**
* **#405**
## How is it implemented?
* **Code** – Adds `process.stdout.write('\x1b[3J\x1b[H\x1b[2J')` in
`terminal.tsx`. Removed reference to `prev` in `
setItems((prev) => [
...prev,
` in `terminal-chat-new-input.tsx` & `terminal-chat-input.tsx`.
## CI / QA
All commands pass locally:
```bash
pnpm test # green
pnpm run lint # green
pnpm run typecheck # zero TS errors
```
## Results
https://github.com/user-attachments/assets/11dcf05c-e054-495a-8ecb-ac6ef21a9da4
---------
Co-authored-by: Thibault Sottiaux <tibo@openai.com>
