[docs] Add example/tutorial repo mod_nosferatu for reactive library page

Author: Menrath

docs/guides/javascript/reactive/index.md

@@ -18,6 +18,14 @@ Third-party plugin developers are free to use any framework they want to impleme
 
 Nevertheless, in terms of reusability, maintainability and user experience the advantages of having a reactive UI are undeniable. For this reason Moodle has an adhoc reactive library that can be used to implement small reactive applications on any Moodle page.
 
+:::tip Example module: moodle-mod_nosferatu
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+GitHub repository: [moodle-mod_nosferatu](https://github.com/ferranrecio/moodle-mod_nosferatu/)
+
+This repository provides a step-by-step tutorial for developers, covering starter, beginner, and intermediate levels. It includes helpful comments, hints, and best practices to aid in development.
+
+:::
+
 ## Reactive pattern highlights
 
 To understand the advantages (and disadvantages) of a reactive User Interface (UI) there are a few major points you must understand about reactivity: