MoveDirectory and CopyDirectory with overwrite

Please support overwriting with `MoveDirectory` and `CopyDirectory`.

A bool parameter in the third position would make sense, wouldn't it? This seems common enough and similar enough to other APIs:

```c#
MoveDirectory(fromPath, toPath, true);
CopyDirectory(fromPath, toPath, false);
```

Or should an entire options class be created in order to specify `Overwrite`?

Start by locating the MoveDirectory and CopyDirectory API entry points and their existing tests. Review how related APIs represent overwrite behavior, then define and test the selected parameter or options design so both operations have the requested overwrite semantics.

Written by the indexing model from the issue text.