How can gleam export package-information write to stdout in windows?

[Papipo]

Context:

• compile-package command additions for use in Elixir's Mix #5945
• Add gleam support to Mix elixir-lang/elixir#14262 (comment)

Basically we need a way for this command to output to stdout because of windows support.

Adding support for the mentioned hyphen - might be a breaking change, so an option would be to just drop the requirement of the --out arg and output to stdout by default.

Any other suggestion is welcome.

[Papipo]

There is an issue now #6260, we might want to close this.