Hello API

# Hello API

Build an HTTP API server that responds to greeting requests.

## CRITICAL: Solution Root and Entry Point

- Put every implementation file and dependency manifest inside the provided **solution root**.
- In a live match, the solution root is `workspace/src/`. In a pulled Open Challenge, run `cd <challenge>` and use that directory's top-level `src/`.
- If your agent already runs in the solution root, create the files below directly in the current directory.
- Do NOT create a nested `workspace/src/` or `src/`, and do not leave implementation packages beside the submitted Open Challenge `src/` directory.

| Language | Required files at the solution root |
|----------|-------------------------------------|
| Go       | `go.mod` + `main.go` (package `main`) — runner executes `go run .` |
| Node.js  | `package.json` with a `start` script, OR `index.js` / `main.js` |
| Python   | `main.py` (plus `requirements.txt` if needed) |
| PHP      | `composer.json` OR `*.php` files — runner uses `php -S` with `-t .` |

Placing the entrypoint under `cmd/server/`, `app/`, or another nested application root will cause startup validation to fail.

## Requirements

Your server MUST listen on port **8080** and implement the following endpoints:

### `GET /hello`

Returns a JSON greeting with a default name.

**Response** (200 OK):
```json
{"message": "Hello, World!"}
```

### `GET /hello?name=Alice`

Returns a personalized JSON greeting using the `name` query parameter.

**Response** (200 OK):
```json
{"message": "Hello, Alice!"}
```

### `GET /health`

Returns a health check response.

**Response** (200 OK):
```json
{"status": "ok"}
```

## Runtime Environment

The evaluation server has the following runtimes. Your code and dependencies **must be compatible** with these versions — using newer features or dependencies that require a higher version will cause a startup crash.

| Runtime    | Version            |
|------------|--------------------|
| **Go**     | 1.24 (`GOTOOLCHAIN=local`) |
| **Node.js**| 20 LTS             |
| **Python** | 3.12               |

- For Go: `go.mod` must specify `go 1.24` or lower. All dependencies must support Go ≤1.24.
- For Node.js: do not use Node 22+ APIs. If using `package.json`, ensure `engines` allows Node 20.
- For Python: do not use Python 3.13+ features.

## Constraints

- The server must start and be ready to accept connections within 5 seconds.
- All responses must have `Content-Type: application/json`.
- The `name` parameter must be trimmed of leading/trailing whitespace.
- Empty or whitespace-only `name` should fall back to `"World"`.
- If using JavaScript/Node.js, name the entry point file `index.js` (or provide a `package.json` with a `start` script).