Punctuation is not included in generated passwords by default. Technically, this is slightly less secure for a given password length, but it prevents syntax-related bugs when a generated password is stored in a (properly-secured) text-based configuration file.
If you know how the generated password will be used, you can add known-safe
punctuation to this when you call
module dauth.random; // ...
immutable(ubyte)defaultPasswordChars; // ...