Improve Modification Orderlines UX

Context: Some merchants choose to delegate the start operation of a modification to their integrators.

Problem: The current Merchant Portal UX does not adequately communicate or support the scenario where the integrator is responsible for starting a modification.

Goal: Update the Merchant Portal UX so that merchants clearly know that they are creating a request, instead of having to work around it by cancelling a start modification operation to achieve the same output.