Preview of the syntax highlighting does not contain examples for all available categories

### Description

It is not easy to understand the syntax highlighting I will get at the end because the preview has a super simple example that does not reflect all available categories

### Use case/motivation

Would be nice to have a more complex example that allows an understanding of what result I will get after all my changes.

### Related issues

_No response_

### Are you willing to submit a pull request?

No

### Code of Conduct

Yes

Start by locating the NetBeans syntax-highlighting preview described in the issue and identify how its current example is provided. Update the preview so it demonstrates all available categories, then verify that the displayed result reflects the available highlighting options.

Written by the indexing model from the issue text.