XSL Transformation

As you know, I'm very fond of this extension. One thing I'm still missing with it, though, is XSL transformations.

I know there are other extensions that can do XSL transformations for you. But I think it would be very neat to have it all in one place. And since this extension comes with Lemminx, which again comes with Xerces that can do XSL transformation, this shouldn't be too hard to do.
(I have been playing around with this extension, my fork can be found here. That pretty much does the trick for my personal use. But for a published extension it has the major downside of not only requiring java, but also a Saxon .jar to do the actual transformation. Again, your extension already ensures java, and it comes with Xerces.)

How do you guys feel about this?
Personally I'd love to see this feature. And once I have a bit more time (not anytime soon, I'm afraid), I'd gladly contribute to that.

(In fact I find it a bit strange that the LSP API does not have the concept of some sort of transformation... I could think of several use cases for that. And if that were the case, it would be extremely easy: The extension could request transformation from Lemminx, which could hand that over to Xerces.)

The issue proposes adding XSL transformations to the VS Code XML extension using its Lemminx/Xerces and Java setup, and references the vscode-xsl-transform approach. Start by reviewing the extension's existing Lemminx integration and define the transformation entry point, runtime requirements, and supported workflow. Done means the feature works without requiring a separate Saxon JAR.