AppendToFile appends data to an existing file.

CopyFile copies a file from src to dst.

Exists checks whether a file or directory exists at the given path.

ListFiles returns a list of all files (not directories) in the given directory.

ReadDirFiles reads the contents of all files in a directory and returns them as a map with file names as keys and file content as values.

ReadFile reads the content of a file and returns it as a string.

WriteFile writes data to a file.