message: doc(es/minifier): Document assumptions
diff: -//! Javascript minifier implemented in rust.
  +//! JavaScript minifier implemented in rust.
  +//!
  +//! # Assumptions
  +//!
  +//! Like other minification tools, swc minifier assumes some things about the
  +//! input code.
  +//!
  +//! - TDZ violation does not exist.
  +//!
  +//! In other words, TDZ violation will be ignored.
  +//!
  +//! - Acesssing top-level identifiers do not have side effects.
  +//!
  +//! If you declare a variable on `globalThis` using a getter with side-effects,
  +//! swc minifier will break it.
  //!
  //! # Debugging
  //!
  