Create index.md for split keyboard project

Added details about the split ergonomic keyboard including layout, title, owner, license, site, and source.

Author: Won-CCS

1209/2358/index.md

@@ -0,0 +1,9 @@
+---
+layout: pid
+title: split keyboard
+owner: Won-CCS
+license: MIT
+site: https://ergogain.co.jp/
+source: https://github.com/Won-CCS/ErgoGain.git
+---
+Split ergonomic keyboard. QMK-based firmware with custom PMW3610 driver.