* Create ko.json
* Update ko.json
* Update i18n.rs
* Fonts: add a Hangul fallback so Korean doesn't render as boxes
Only the first CJK font found was loaded, and on Windows and macOS that is
a Japanese font without Hangul (Meiryo, Hiragino). Load the first readable
font of each group: the existing CJK list, then Malgun Gothic (Windows),
Apple SD Gothic Neo (macOS) or Nanum Gothic (Linux). Also rustfmt the
Korean catalog test.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RjGw4gA5ZvKrU8MQP6sBgT
---------
Co-authored-by: bherbruck <brennen.herbruck@gmail.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
