//! Unit systems.
//!
//! This module provides predefined units from various unit systems:
//!
//! - [`si`] — SI (International System of Units)
//! - [`cgs`] — CGS (Centimeter-Gram-Second)
//! - [`astrophysical`] — Astrophysical units
//! - [`imperial`] — Imperial/US customary units
//! - [`logarithmic`] — Logarithmic units (magnitudes, decibels, dex)
/// Shorthand module for quick unit access.
///
/// ```
/// use iridium_units::systems::u;
///
/// let speed = 10.0 * (u::M / u::S);
/// ```