V01.00 — Volume I Overview: Observerhood from Constraint, Viability and Recursive Reliability

V01.00 states the purpose, thesis, architecture, claims, non-claims, limitations and pressure points of Volume I: Observerhood, the first substantive research arc of the Mirror Programme. Volume I investigates observerhood as a derived organisational condition in which a bounded physical or computational system preserves viability by maintaining world-models, self-models, reliability estimates, memory governance and physically supported continuity under perturbation. This overview maps the Theory Arc, Mathematics Arc, Computational Observerhood Labs and Physics Support Arc of Volume I. It is a volume-level orientation document rather than a technical proof paper.