message: add docs for Fiber properties
diff: @@ -39,15 +39,38 @@ export class Descriptor {
  export type Fiber<E, A> = Runtime<E, A> | Synthetic<E, A>
  export interface CommonFiber<E, A> {
  + /**
  + * Awaits the fiber, which suspends the awaiting fiber until the result of the
  + * fiber has been determined.
  + */
  await: UIO<Exit.Exit<E, A>>
  + /**
  + * Gets the value of the fiber ref for this fiber, or the initial value of
  + * the fiber ref, if the fiber is not storing the ref.
  + */
  getRef: <K>(fiberRef: FiberRef<K>) => UIO<K>
  + /**
  + * Inherits values from all {@link FiberRef} instances into current fiber.
  + * This will resume immediately.
  + */
  inheritRefs: UIO<void>
  + /**
  + * Interrupts the fiber as if interrupted from the specified fiber. If the
  + * fiber has already exited, the returned effect will resume immediately.
  + * Otherwise, the effect will resume when the fiber exits.
  + */
  interruptAs(fiberId: FiberID): UIO<Exit.Exit<E, A>>
  + /**
  + * Tentatively observes the fiber, but returns immediately if it is not already done.
  + */
  poll: UIO<O.Option<Exit.Exit<E, A>>>
  }
  export interface Runtime<E, A> extends CommonFiber<E, A> {
  _tag: "RuntimeFiber"
  + /**
  + * The identity of the fiber.
  + */
  id: FiberID
  }
  