Add pagination to Shopify integration

[brookewp]

This implements the pagination feature (@chriszarate added in #338) to our Shopify integration.

To get the total product count, we'd need access to read_products which requires authenticating with OAuth. To avoid this, I've made total_items optional and added has_next_page, so we can paginate through products one page at a time:

Screen.Recording.2025-02-24.at.5.49.25.PM.mov

I also exposed setPerPage so the items per page can be updated, which makes going through the products a lot faster. This will also update for any sources with pagination set up (e.g. the art institute).

[chriszarate]

This doesn't quite work. The part in parentheses will always return a non-null value, so the 1 is never reached

[brookewp]

Right. What do you think of using Math.max?

totalPages: totalPages ?? ( hasNextPage ? page + 1 : Math.max( 1, page ) ),

[chriszarate]

can you update the supports*Pagination variables above to take into account the statement we made in the schema? "either total_items or has_next_page must be defined"

[brookewp]

Something like this?

	const supportsPagination =
		supportsCursorPagination ||
		supportsPagePagination ||
		supportsOffsetPagination ||
		totalItems ||
		hasNextPage;