acopw-cli: A simple and secure password generator

acopw-cli is a fast, no-frills command-line utility for
generating secure random passwords, Diceware passphrases,
and numeric PINs.

It uses Go's crypto/rand package for secure randomness,
avoiding selection bias, and provides a curated word list with
over 23,000 words for Diceware.

Features:
- Generate secure random passwords with configurable length
- Create Diceware passphrases with custom separators
- Generate numeric PINs
- No external dependencies beyond Go itself
