Merge pull request #45 from control-toolbox/update-readme-2025-09-22

Update README (2025-09-22) with latest ABOUT.md, INSTALL.md, CONTRIBUTING.md and badges

Author: ocots

CONTRIBUTING.md

@@ -0,0 +1,14 @@
+## Contributing
+
+[issue-url]: https://github.com/control-toolbox/Tutorials.jl/issues
+[first-good-issue-url]: https://github.com/control-toolbox/Tutorials.jl/contribute
+
+If you think you found a bug or if you have a feature request / suggestion, feel free to open an [issue][issue-url].  
+Before opening a pull request, please start an issue or a discussion on the topic. 
+
+Contributions are welcomed, check out [how to contribute to a Github project](https://docs.github.com/en/get-started/exploring-projects-on-github/contributing-to-a-project). If it is your first contribution, you can also check [this first contribution tutorial](https://github.com/firstcontributions/first-contributions). You can find first good issues (if any 🙂) [here][first-good-issue-url]. You may find other packages to contribute to at the [control-toolbox organization](https://github.com/control-toolbox).
+
+If you want to ask a question, feel free to start a discussion [here](https://github.com/orgs/control-toolbox/discussions). This forum is for general discussion about this repository and the [control-toolbox organization](https://github.com/control-toolbox).
+
+>[!NOTE]
+> If you want to add an application or a package to the control-toolbox ecosystem, please follow this [set up tutorial](https://github.com/orgs/control-toolbox/discussions/65).