HγC O3: Comparative Estimators for Structured Near-Critical Populations in Galactic Phenomenology

This paper establishes the first comparative estimator layer for structured near-critical populations in galactic phenomenology within the HγC framework. Earlier N-series work established band existence, band structure, and observational diagnostic language; O1 fixed the first explicitly galactic diagnostic morphology layer; and O2 stabilized the first controlled comparative morphology framework for relating differently populated galactic realizations within a shared near-critical family. O3 takes the next justified step by reformulating comparative center, breadth, asymmetry, and tail-supported persistence in terms of weak semi-phenomenological estimators. The aim is not to replace the comparative morphology language established in O2, but to provide the minimal intermediate layer by which differently populated galactic realizations may be compared more narrowly without collapsing the problem back into fit-first logic. Support, neutral variation, and tension are correspondingly reformulated at the estimator level as the first controlled judgment language for assessing whether comparative morphology remains observationally stable under narrower estimator-based reading. The scope of the paper is deliberately limited. O3 does not perform full catalogue-level fitting, reconstruct galaxy-by-galaxy hidden regime-space populations, derive the bridge-variable ensemble microscopically, derive the characteristic acceleration scale from first principles, enter the temporal reorganization sector associated with the W-series, or integrate the galactic line with the projected-profile morphology of the weak-field lensing branch. Instead, it stabilizes the first comparative estimator layer required before later narrower calibration can become meaningful.