Jet is a frozen dataclass; with_amplitude returns a validated copy, so
region/field/profile cannot drift from the cached per-link shapes and
amplitude cannot bypass validation. CurvedLinkSoA.set_jet_amplitude and
Simulation.set_jet_amplitude replace the Jet (Simulation also updates the
registered list so later geometry syncs keep the amplitude). Reject
non-finite hits; document edge rule (|s|<1 exclusive, radial/along
bounds inclusive). Fix the clipped-q test selector to receiver (9,5)
dir 8, as in test_surface_actuation.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>