idrefers to the id of the object in question, so for product.update it is the product id, for page.update the page id etc.
metafieldsarray is the up-to-date set of metafields for the id. The type of
valuedepends on the type of the metafield - for repeatable fields, the value will always be an array.
Control panelbutton to open a new dialog to add the HTTPS endpoint(s) to handle the webhooks.
200 OKas quickly as possible.