[Woo POS] Revert `WooCommercePOS` framework

[iamgabrielma]

Ref: 1fiXjeKkf_D28tRghYbwjRjo5boDrwQCXMkRH1jYw-WQ-gdoc

Revert the recently merged framework to align with the decision not to further pursue modularization at this point in time.

[dangermattic]

Thanks for reporting! 👍