Drive with bare hands in the cockpit

- With tracked hands on, a hand driving khr/simple_controller with camera-tracked joints is bare:
  latched through wheel_tracking_grace (Meta drops the select action while a hand is lost),
  cleared as soon as a controller's squeeze is back. Its palm joint stands in for the grip and a
  grasp from the middle, ring and little fingers' flexion (0 below 1.2 rad, 1 from 3.0) for the
  squeeze, so closing a hand on the rim takes hold under the wheel's own press and release. The
  grasp never reaches the game's buttons.
- In a cockpit race a bare hand holding the wheel holds the gas (A / South) and a pinch from a free
  bare hand uses an item (Z / L) once the hand has been off the wheel for 0.15 s. Only while the
  game has the remote's pointer off: KPAD publishes the game's pointer switch for the VR remote,
  so the pause menu and the results keep a right pinch as A. The pacing thread logs each change,
  to confirm on the headset that MKW turns the pointer off while driving.
- A held bare hand keeps its last joints drawn through a short loss; bare hands get no haptics.
  The headset panel's readout shows grasp, hold and pinch. Docs: OPENXR.md.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

runtime/src/settings_overlay.cpp

@@ -1192,8 +1192,11 @@ void DrawVrSteeringWheelSettings() {
         ImGui::SetTooltip(
             "%s", mkw::vr::OpenXRHandTrackingAvailable()
                       ? "The cockpit hands follow your own. Holding the controllers, the fingers follow "
-                        "their touch sensors; put the controllers down and the headset's cameras track "
-                        "your hands. Needs hand tracking on in the headset's settings."
+                        "their touch sensors. Put the controllers down to drive with bare hands: close a "
+                        "hand on the wheel to hold it, which also holds the gas; pinch with a free hand "
+                        "to use an item; pinch with your left palm facing you to pause. In menus, a "
+                        "right pinch is A. Choose Automatic drift. Needs hand tracking on in the "
+                        "headset's settings."
                       : "The cockpit hands follow your own, from the controllers' touch sensors or, "
                         "with the controllers put down, the headset's cameras. This session started "
                         "with hand steering and tracked hands off, so it applies after a restart.");