NOTICE.md and THIRD-PARTY-NOTICES.md credit @YuriRestia (PR #70) for the English UI strings and fallback
translations, note that PR #70's ak-spa-database.pages.dev texts are not used and that arknights.wiki.gg is
CC BY-SA 4.0, and name the EN data mirrors (ArknightsAssets/ArknightsGamedata, Kengxxiao/ArknightsGameData_YoStar).
DATA.md: data/i18n/en.json is written by tools/build-i18n.mjs (rerun after a text-changing build).
PLAYING.md: the 中文 / English switch.
