jsdev-mario/ReactGoogleMapExample — reverse-engineered prompt

Build me a simple React app that shows a Google Map in the browser. I want it to load a map, place markers on it, draw a route line between locations, and let me drag and drop a marker to move it around on the map.

Please keep it as a clean demo that I can run locally with npm start. Make the page easy to understand, with the map taking up most of the screen and any basic controls or labels kept simple. If a Google Maps API key is needed, set it up in a way where I can add my own key without digging through the whole project.

Use the current Google Maps React docs if you need to look anything up. The goal is just a working example for displaying a map, drawing a route, and moving markers around.