P51 v2 — Errata: Corrected a_max/M = 0.356–0.503

"Corrects Table 3 of P51 v2.0: value 0.7–0.9 was R/M_geom (=1/C), not a_max/M. Correct value is 0.356–0.503." Correction to v1.0. C = 0.44 was incorrect (used ρ_c ≈ 2.6 ρ_nuc implicitly). Correct value with ρ_c = 7.4 ρ_nuc gives C ≈ 0.63–1.27. Ergoregion is exterior to the object for all masses. Ergoregion instability claim retracted. Rotational stability recovered via P60 (geometric suppression mechanism). Analytical verification that CCEGA black stars (4.56–12.0 M☉, C ≈ 0.44) are rotationally stable. Light ring confirmed at r = 3GM/c². Ergosphere buried inside stellar surface for all masses at maximum spin. No Friedman (1978) ergoregion instability. Maximum rotation 0.76–2.0 kHz. Stability is structural consequence of ρ_c = 7.4 ρ_nuc.