## 0.1.0

* Halkyon Learn's look, for every Halkyon app:
  `appTheme(brightness, extensions: …)` with the hand-written light and dark
  schemes around cobalt and copper, `Brand`, `ThemeExtras` (success, warning,
  info), `PaletteColor`, `FittedSnackBars`; Noto Sans bundled
  (`appFontFamily`, `appFontFallback`, `appFontFallbackFor`,
  `registerFontLicenses`); `WindowSize` and `readableContentMaxWidth`; the
  shared widgets (sheets, frames and gradients, spinners, fields, lists,
  `BrandWordmark` and `LaunchScreen` taking an app's word and icon) with their
  texts in English and German (`HalkyonUiLocalizations`).