docs: add note about baked-in templates in README (#1735)

Co-authored-by: Shubham <b4mshubham@gmail.com>
Co-authored-by: Lukasz Gornicki <lpgornicki@gmail.com>

Author: shubham220420

README.md

@@ -65,6 +65,9 @@ There is a large number of templates that are ready to use and are officially su
 
 You can find above templates and the ones provided by the community in **[this list](https://github.com/search?q=topic%3Aasyncapi+topic%3Agenerator+topic%3Atemplate)**
 
+> [!IMPORTANT]
+> **Experimental Feature:** AsyncAPI Generator also comes with **baked-in templates** - official templates shipped directly inside the Generator (`@asyncapi/generator`). They cover code, docs, configs, and SDKs, and are maintained under [/packages/templates](packages/templates) directory, following a strict, opinionated structure for consistency and ease of maintenance. This feature is not recommended for production use. For those who want to try them out or learn more, see the [Baked-in templates documentation](https://www.asyncapi.com/docs/tools/generator/baked-in-templates).
+
 ## Filters
 
  `apps/nunjucks-filters` library contains generator filters that can be reused across multiple templates, helping to avoid redundant work. These filters are designed specifically for Nunjucks templates and are included by default with the generator, so there's no need to add them to dependencies separately.

apps/generator/README.md

@@ -26,3 +26,6 @@ There is a large number of templates that are ready to use and are officially su
 <!-- TEMPLATES-LIST:END -->
 
 You can find above templates and the ones provided by the community in **[this list](https://github.com/search?q=topic%3Aasyncapi+topic%3Agenerator+topic%3Atemplate)**
+
+> [!IMPORTANT]
+> **Experimental Feature:** AsyncAPI Generator also comes with **baked-in templates** - official templates shipped directly inside the Generator (`@asyncapi/generator`). They cover code, docs, configs, and SDKs, and are maintained under [/packages/templates](packages/templates) directory, following a strict, opinionated structure for consistency and ease of maintenance. This feature is not recommended for production use. For those who want to try them out or learn more, see the [Baked-in templates documentation](https://www.asyncapi.com/docs/tools/generator/baked-in-templates).