Variable printBannerConst

Prints the startup banner once per process. The banner is a permanent part of this package and cannot be disabled:

• TTY: full color banner (24-bit true-color when the terminal supports it, 256-color otherwise; OSC-8 clickable repo link)
• non-TTY (CI/pm2/pipes): a single plain-text signature line (no ANSI)
• NO_COLOR: banner prints without ANSI styling (color opt-out only)