## `obiutils.DownloadFile` — Semantic Feature Overview

- **Core Functionality**: Downloads a file from a given URL to a specified local path.
  
- **HTTP Client Behavior**:
  - Uses `http.Get()` for simple, synchronous GET requests.
  - Validates the HTTP status code; aborts on non-200 responses with a descriptive error.

- **Resource Management**:
  - Ensures proper cleanup via `defer resp.Body.Close()` and `defer out.Close()`.
  
- **Progress Tracking**:
  - Integrates [`progressbar`](https://github.com/schollz/progressbar) to display real-time download progress.
  - Uses `DefaultBytes()` for a human-readable, byte-based indicator (e.g., "downloading 12.3 MB / 45.6 MB").

- **Efficient I/O**:
  - Leverages `io.Copy()` with an `io.MultiWriter` to stream data directly from the HTTP response body into both:
    - The target file (`out`)
    - The progress bar (to update on each chunk written)

- **Error Handling**:
  - Returns early with wrapped errors for network failures, HTTP non-success codes, or file I/O issues.

- **Simplicity & Usability**:
  - Minimal API surface: only two arguments (`url`, `filepath`).
  - No external configuration needed — ideal for CLI tools or batch scripts.

- **Assumptions**:
  - No authentication, redirects, proxies, timeouts, or retries are implemented.
  - Designed for straightforward downloads where robustness is secondary to simplicity.

- **Typical Use Cases**:
  - CLI utilities, build scripts, CI/CD pipelines.
  - Prototyping or internal tools where advanced download features are unnecessary.

- **Limitations**:
  - Not suitable for large-scale or production-grade downloads without enhancements (e.g., retries, concurrency control).