Notation changed from phibar to M throughout. The action used for <S>/V is written out explicitly (no constant lambda V). The autocorrelation table lists tau_int of M, |M|, S and the nearest-neighbour correlator E, the slowest observable found in a scan of 13 quantities. Supersedes PR #2.
README: observables as in arXiv:2607.08505, autocorrelation table, citation (#2)
