Replace PiRTO-II-based mailbox protocol and hardware notes with the
Minty-derived fujicard implementation: mailbox moved to $9C00-$9F3F
to coexist with JLP, corrected register layout, ROM-boot-over-mailbox
and BOOTSEL doorbell sections, and known-gaps notes. Hardware page
renamed to FujiCard Hardware Notes with a corrected RP2350 pinout and
a licensing section separating the firmware GPLv3 grant from the
still-unlicensed PCB; old page title left as a redirect stub.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TwAEz7TNCwmboxNPwgNt1s
