test_spacecraftHubOnlyFastPath

Unit tests for the automatic hub-only spacecraft dynamics fast path.

When no state effectors are attached and point \(B\) is colocated with the hub center of mass, Spacecraft can bypass the general back-substitution matrix assembly and ask HubEffector to compute direct rigid-body derivatives. This test validates the resulting translational and rotational dynamics against a simple analytic case.

test_spacecraftHubOnlyFastPath.test_spacecraftHubOnlyFastPath_matchesAnalyticForceTorque()

Hub-only fast path must reproduce direct rigid-body force/torque motion.