feat(checkout): CHECKOUT-7176 Displaying the Hidden Cart Source Input Field on PDP page

[bc-mackxu]

What?

Displaying the Hidden Cart Source Input Field on PDP page

Requirements

• CHANGELOG.md entry added (required for code changes only)

Tickets / Documentation CHECKOUT-7176

The "Add to Cart" button on the PDP page initiates a call to the remote/v1/add endpoint for adding items to the cart. To facilitate the creation of a cart with the order source set to 'buyButton,' it will display the hidden cart source input field, enabling the posting of the cart source value to the endpoint.

Here are all the scenarios related to determining whether the order source needs to be set as "buy_button." This PR is specifically focused on addressing scenario 5.

	Scenario	Redirect To	Is set order source buy button?
1	Not cart in the session	Checkout	Yes
2	A cart in the session	Checkout	No
3	Not cart in the session	Cart	No (to change Yes in another PR)
4	A cart in the session	Cart	No
5	Not cart in the session	PDP page → click add product	No (this PR will display cart_source and able to send to remote/add endpoint)
6	A cart in the session	PDP page → click add product	No
7	Secondary cart	PDP page → click wallet button	No

Screenshots

Add item to cart on PDP when there is no cart in the session - order source will set as buy button

Screen.Recording.2023-09-05.at.5.30.08.pm.mov

Add item to cart on PDP when there is a cart in the session - order source will not set as buy button

Screen.Recording.2023-09-05.at.5.37.10.pm.mov

@bigcommerce/team-checkout

[BC-krasnoshapka]

@bc-mackxu have you considered if cart_order_source attribute should be added to dev docs?

[bc-mackxu]

@BC-krasnoshapka Thank you for reviewing. Yes, I think we should also add it to dev docs

[bc-mackxu]

Thank you for review and approval @bc-vlad-dlogush and @BC-krasnoshapka. Could you help to merge it when you have time please? I don't have permission to merge on this repo. Thank you again.