Phase 3 - Fix RG keyboard clarity

1. Make the RG keyboard overlay self-explanatory:
   • “D-pad move”
   • “A pick”
   • “B back”
   • “X space”
   • “Y del”
   • “L chips”
   • “R abc/ABC/123”
   • “Start send”
   • “Select keyboard/help”
2. Keep text short enough for 640x480.
3. Consider a dedicated ?/help mode bound to Select if F11 is not reliable.
4. Confirm Start reaches F12 in both paths:
   • hermes.gptk
   • pygame joystick mapping in herms_sdl_client.py
   • VirtualKeyboard.tsx handling f12
5. If gptokeyb and pygame both inject controls, decide which layer owns input and document it. Duplicate events can make the keyboard feel broken.