ExtFriend shell cover

This is a shell case for "ExtFriend," which connects the WonderSwan to a PC's USB port.

Parts needed for this build:
- RP2040-Zero
- HDMI male connector
- M2x5mm screw

Please refer to the X-Thread link below for production instructions.
https://x.com/SourceK_mnst/status/1934555813831745556

"ExtFriend" is an open source project released by asie (https://x.com/cbrzeszczot).
In addition to serial communication, it also has an audio capture function.
When connected to a PC, it is recognized as a microphone device called "ExtFriend UAC2," allowing you to capture audio from the WonderSwan.

For more information, see the link below.

ExtFriend Project:
https://github.com/asiekierka/ws-extfriend
GPL-3.0 license

It can also be used for "ws_online," the WonderSwan online communication web application that I released.

ws_online Project:
https://github.com/SourceK78/ws_online
MIT license