akashchepe/xml-viewer ? reverse-engineered prompt

Build me a standalone Angular 17+ component that takes a raw XML string and displays it in a nice readable tree view. I want the XML to be pretty printed with proper indentation, syntax highlighting for tags, attributes, values, comments, CDATA, and processing instructions, plus collapsible nodes so people can expand or collapse parts of the document. Please include simple Expand All and Collapse All controls, and make it look good in a dark theme by default.

It should handle empty or missing XML gracefully with a friendly placeholder instead of breaking. This is meant to be lightweight and easy to drop into an app, so keep it dependency free if you can. If you need to check current Angular docs or best practices while building it, go ahead and look them up online.