Implement B2b category

[WeizhengSap]

B2B has category API. We need implement it in SPA, and replace it with the b2c one.

[WeizhengSap]

B2b has category API. Without it, PLP works as well (using b2c search). But, we still can implement it in SPA. (This API may be moved to core.)

This is from Frank: If there is nothing B2B specific in that categories API and it only happens to be implemented in a B2B module and in a future SCC deployment ALL extensions are active by default, then why would we not slowly remove "B2B" tags from such APIs? there is a difference between:

• what the functionality is intended for: b2b/b2b or both like this case
• where the functionality was implemented

and the latter is getting less and less important and we could easily move up the API to core, so should not have any B2B naming in it. It is about API documentation in the end, not about how and where it is implemented imo.

[Xymmer]

From #7715 The B2B API has the following endpoint to get products by Category:

/{baseSiteId}/categories/{categoryId}/products

Unlike B2C, which uses the generic products/search endpoint.

If a customer only implements B2B (and no B2C) and he wants to use the B2B Categories endpoint to find all of the products by Category, we need to provide support for the given endpoint. Therefore, we need to implement the usage of this endpoint in Spartacus (which will be addressed by #6591)

It is worth to say that at the moment, PLPs and PDPs work fine using the products/search endpoint when filtering by Category. The only small caveat is that we are not displaying the right Category name on the PLPs (and we need a fix for it)

To @bgambocjaviniar comment: For generic product search (from the search box for example) we will use the B2B product Search endpoint, which is the same as the B2C one

[Xymmer]

we agreed that this one is stretch, so it's not in tribe board but in B2B prioritization board