Quantum Chess rules

This document defines version 1.0 of the rules of Quantum Chess, which release 1.22.0 of the game implements. It covers the quantum state, the gates each move applies, which moves are legal, how the game resolves a measurement, and how a game ends. It is meant to be cited. Each version of the rules gets its own archived record that never changes, so a result that depends on the rules can name the version it was proved against. Section 11 lists what has changed since the first published rules of 2019.