Presentation-only reorder (user 2026-09-17): the Depth anchor select
and its three gray-out-able sliders (Depth strength, Depth spacing,
Base ring radius) move below Friction to the very bottom of the
Physics section, so the always-active general forces come first and
the conditional group reads as a self-contained sub-section at the
end. No schema, wiring, or behavior changes — verified identical DOM
order live, gray-out still follows the stored depth mode.