///|
/// MoonFlags is a small feature flag and rollout engine for MoonBit.
///
/// The public API is split across the package files:
/// - `types.mbt` defines flag, rule, rollout, and result data types.
/// - `context.mbt` builds evaluation contexts.
/// - `condition.mbt` evaluates attribute matchers.
/// - `engine.mbt` evaluates flags and flag sets.
/// - `validate.mbt` validates reusable flag definitions.