Default bindings: pad-mandatory axes, full keyboard button field

Rework the shipped default profile around a required Xbox controller,
refined from live-game testing:

- All five axes are pad-only now (left stick / triggers / right stick);
  the key-axis bindings (arrows/WASD-style deflect and rate) are gone
  from the defaults, though the grammar remains supported.
- Keyboard becomes the button field, geometry mirroring the panel:
  number row + QWERTY row = upper MFD bank, home + bottom rows =
  lower MFD bank as two 4-key blocks with an unbound gap key (G / B)
  standing in for the panel keypad gap, F1-F6 / F7-F12 = the
  Secondary / Screen columns top-to-bottom (0x16/0x17, 0x1E/0x1F
  deliberately unmapped), numpad = the full internal keypad with the
  hex keys on the operators (/ * - + . Enter = A-F).
- Hat rides the arrow keys, Main stays on Space; Pinky / Middle /
  Upper / Panic are pad-only so no panic key sits inside the MFD field.
- Pad B and LeftShoulder swap to Middle / Panic.
- Rest of the throttle column and the external keypad stay unmapped.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

README.md

@@ -29,9 +29,14 @@ controls:
   bindings* applies edits live). Keys and pad buttons press any RIO address;
   pad sticks/triggers and keys drive the axes in each axis' realistic travel
   window, with deflect (spring-back), rate (throttle-style, position holds),
-  deadzone, and invert options. Defaults: arrows = stick, W/S = throttle,
-  Q/E = pedals, numpad = internal keypad, IJKL/Space = hat + main, left
-  stick / triggers / right stick = stick / pedals / throttle on the pad.
+  deadzone, and invert options. The default profile makes the controller
+  mandatory: all five axes live on the pad (left stick / triggers / right
+  stick = stick / pedals / throttle) and the keyboard covers the button
+  field — number row + QWERTY row = the upper MFD bank, home + bottom
+  rows = the lower MFD bank (4-key blocks split by an unbound gap key),
+  F1–F6 / F7–F12 = the Secondary / Screen columns, numpad = internal
+  keypad (hex keys on the operators), arrows + Space = hat + main, with
+  ABXY / dpad / shoulders on the pad's named buttons.
 
 ## Wire behavior