wassgha/digital-signage ? reverse-engineered prompt

Build me a simple self hosted digital signage app where I can manage what shows up on a TV screen from a browser admin panel.

I want an admin area where I can create and arrange widgets on a flexible grid, drag them around, resize them, and change their settings. The display side should be full screen and update automatically when content changes, so I do not have to keep touching the screen once it is set up.

Please include the built in content types this project is meant to have, like slideshow, weather, announcements, web embeds, YouTube embeds, standalone images, lists, and a simple congratulations style message. The slideshow should support different kinds of slides and let me set durations and titles. It should be self hosted, use a MongoDB database, and be easy to run locally with a setup step and a dev server.

If you need current library details, look them up online and keep the app modern and working.