feat: add resolver prop to SliceZone for backwards compatibility with next-slicezone

[angeloashmore]

Types of changes

• Chore (a non-breaking change which is related to package maintenance)
• Bug fix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Description

This PR adds a resolver prop that matches that of next-slicezone. This change makes the migration path smoother for users upgrading existing projects.

It is marked as deprecated in favor of the components prop. @prismicio/react's <SliceZone> will ultimately replace next-slicezone.

In a future major version, the resolver prop will be removed.

For reference, this is the type signature of the resolver function:

/**
 * Arguments for a `<SliceZone>` `resolver` function.
 */
type SliceZoneResolverArgs<TSlice extends SliceLike = SliceLike> = {
	/**
	 * The Slice to resolve to a React component.
	 */
	slice: TSlice;

	/**
	 * The name of the Slice.
	 */
	sliceName: TSlice["slice_type"];

	/**
	 * The index of the Slice in the Slice Zone.
	 */
	i: number;
};

/**
 * A function that determines the rendered React component for each Slice in the
 * Slice Zone.
 *
 * @deprecated Use the `components` prop instead.
 *
 * @param args - Arguments for the resolver function.
 *
 * @returns The React component to render for a Slice.
 */
export type SliceZoneResolver<
	TSlice extends SliceLike = SliceLike,
	TContext = unknown,
> = (
	args: SliceZoneResolverArgs<TSlice>,
) => SliceComponentType<TSlice, TContext>;

Checklist:

• My change requires an update to the official documentation.
• All TSDoc comments are up-to-date and new ones have been added where necessary.
• All new and existing tests are passing.

🦊