retejs/rete ? reverse-engineered prompt

Build me a JavaScript framework for visual programming that lets me create node based editors and workflow builders in the browser.

I want a system where users can drag nodes onto a canvas, connect them with lines, and build visual logic for data flow and control flow. It should be easy to plug in different rendering layers and UI frameworks, and it should feel like a solid base for making custom graph editors, not just a demo.

Please make it clean, well organized, and written in TypeScript. Include enough examples so I can see how to define nodes, connect them, and process a graph. If anything depends on current best practices or up to date docs, look that up online as needed.

Also include tests where it makes sense, and make sure the project is set up so someone can start building a real visual programming app from it without too much extra work.