The Rating (jig-rating) is a form control for picking a numeric score by
clicking a row of symbols, dragging across them, or using the keyboard. Bind
value and set count for the number of symbols and step for the granularity
(use 0.5 for half symbols). It exposes the slider role.
Set step to allow fractional values such as half symbols.
Provide an <ng-template #indicator> to render each symbol yourself. It receives
the fill ratio ($implicit, 0..1) and the symbol index.
readonly, disabled, and invalid states.
jig