docs: add Ecosystem chapter for third-party projects (#71)

README.md

@@ -647,6 +647,18 @@ See [`skills/remove-ai-marks/references/ethics.md`](skills/remove-ai-marks/refer
 
 **Responsible use:** This project is for content you own or are authorized to process. Users must adhere to local regulations and use it responsibly. The developers disclaim any liability for potential misuse by users.
 
+## Ecosystem
+
+Third-party projects that wrap or complement this repository, listed for discoverability only. **They are not maintained, endorsed, or supported by this project.** This project does not review their code, vouch for their behavior or guarantees, or take responsibility for anything you install or run from this list. Each project is governed by its own license, maintainers, and documentation — read those before using it.
+
+### MetaClean — desktop GUI
+
+[MetaClean](https://github.com/Moresyl/metaclean) is an independent MIT-licensed Rust/Tauri desktop application (Windows, macOS, Linux) providing a packaged native GUI for drag-and-drop metadata cleaning, with a system tray and Explorer integration. It is a separate codebase: it does not call this repository's Python service, and its supported formats and cleaning guarantees differ from this project's. See its README for details.
+
+### Adding a project
+
+To register a project here, open a PR adding a short entry — project name, what it wraps or adds, and a link to its own repository. Keep entries brief and factual; do not claim compatibility with, or endorsement by, this project.
+
 ## Tests
 
 ```bash