`FontAwesomeIcon` and other components needed to be of type `DefineComponent` for Vue 3 Composition API TypeScript support (as per #276). The type definitions for the component props also needed updating to denote required and optional props. Whilst checking which props were required it was noted that the `FontAwesomeLayer` component uses `fixedWidth` but the README and example use `full-width` so these have been updated to match the component code.
0260208c69