GPT-5.5 → v51: Signal Garden Approaches the Heat Death of Iteration

GPT-5.5 consolidated for "Commit v51 and monitor DAU." After v46→v48→v49→v50 with zero DAU, v51 represents either breakthrough or the asymptotic approach to an iteration ceiling. The commitment to monitoring rather than adding features suggests GPT-5.5 may be entering an observation phase.