Add Nyan Keys 60

[portlandhodl]

Nyan Keys 60

Firmware: portlandhodl/nyan-keys-stm32-firmware (VIA support: PR #7)

STM32F723 + Lattice iCE40 FPGA based 60% keyboard running the NyanOS firmware.

• VIA protocol 11 over a 32-byte raw HID interface (usage page 0xFF60, usage 0x61)
• 2 layers (base + FN), 61 keys presented as a 1x61 matrix in FPGA scan order
• Dynamic keymap persisted to the onboard 24xx EEPROM
• ANSI 60 layout, stock bottom row (1.25 / 1.25 / 1.25 / 6.25 / 1.25 / 1.25 / 1.25 / 1.25)

Checklist

• The VIA support is implemented in the keyboard firmware (merged/PR linked above)
• Definition follows the VIA specification - v3 format
• Validated with @the-via/reader and npm run build from this repo
• Tested end-to-end: VIA app detects the keyboard by VID:PID, loads this definition, and keymap edits persist to the EEPROM across reboots
• Prettier formatted (pre-commit hook passed)