ShadowArcanist/netviz ? reverse-engineered prompt

Build me a browser app where I can design network architectures visually and turn them into animated request flows.

I want to be able to drag components like servers, proxies, databases, and load balancers onto a canvas, connect them with lines, and then edit the selected item in a side panel. It should support preset templates, custom blocks with my own icons, duplicating items, and undo and redo. I also want to build simple animations that show requests moving through the system, with a preview mode and an option to follow the camera along the path.

Make it feel polished, with both dark and light theme support, and let me save my work locally in the browser so there’s no backend needed. It should also be able to export the canvas as an image. If you need to check current docs for any library details, look them up online.