fix(cli): Detect TTY for interactive mode instead of hardcoding true

[RobertWHurst]

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Summarize your changes:

A very simple change to detect if stdin belongs to a proper tty before enabling interactive mode. This makes running forge in non interactive contexts possible.

[erickzhao]

seems legit to me, thanks https://nodejs.org/api/process.html#a-note-on-process-io

[erickzhao]

Hey @RobertWHurst, this organization requires you to sign your commits before a PR is mergeable. Do you mind rebasing your PR with signed commits so I can merge? Thanks!

[RobertWHurst]

absolutely. I'll do that soon. Sorry for the delayed response - busy week.