A1essandro/MapMaker ? reverse-engineered prompt

Build me a small C# library and simple test app that can generate terrain heightmaps.

I want to be able to create a map using either a diamond square style algorithm or a noise based generator, then get back a 2D array of height values I can use for terrain, maps, or other procedural world stuff. It should support both a normal call and an async version, since I may want to generate bigger maps without blocking.

Please keep the API easy to use, with a simple config for things like map size and persistence, and make sure the generated results are reproducible and sensible for different sizes. Include a quick console example that shows how to create a generator, run it, and print or inspect the height data. Add a few basic tests too, just to verify the generators return the expected shape and values. If you need to look up current docs or best practices, go ahead.