**What**
- Implements the admin create end point
- Service implementation of the create method and the retrieveActive as well as the totals computation
- Improve compute line items
- client
- medusa-js api
- medusa-react mutations hooks
**Tests**
- Unit tests of the create end points
- Unit tests of the service create method
- Integration tests for admin that also take into account totals computations
- client
- medusa-js tests
- medusa-react hooks tests
FIXES CORE-491
**What**
- Implements the admin/store retrieval end point
- Service implementation of the retrieve method
- Service implementation of the computeLineItems method which aggregates the right line item based on the changes that are made
- client
- medusa-js api
- medusa-react queries hooks
**Tests**
- Unit tests of the retrieval end points
- Unit tests of the service retrieve method and computeLineItems
- Integration tests for admin/store
- client
- medusa-js tests
- medusa-react hooks tests
FIXES CORE-492
