v0.16.0

Features

• wax doctor now checks whether a newer stable version of wax is available and suggests running wax update self when applicable.
• wax update accepts shorthand actions: wax update s|self (stable) and wax update sn|self-nightly (nightly from GitHub HEAD).

Breaking Changes

• Stable self-update no longer downloads a prebuilt binary from GitHub releases; it now installs via cargo install waxpkg --bin wax (requires cargo to be available).