dmcinnes/dead-valley ? reverse-engineered prompt

Build me a browser game called Dead Valley, a top down zombie survival game with a Grand Theft Auto style feel. I want to be able to drive or move around a map, fight zombies, and survive in a ruined town with a simple HTML5 game loop.

Please make it run from a local web server, not just by opening the file directly in the browser. Keep the code organized in a way that makes sense for a larger JavaScript game, and include the basic game assets, map data, and any helper code needed to make it playable.

I also want a simple in browser map editor so I can place tiles on a grid, paint with the mouse, and edit the JSON maps used by the game. If you need to look up current docs online for the best way to wire things together, go ahead.

If there are existing tests or a test runner, keep them working too.