[RFC] Nest carton into shipment view
Description
WIP
Cartons belong to a shipment. Also they can belong to mulitple orders, but IMO this feature should be moved into an extension instead.
This declutters the order shipments view in order to remove confusion around shipments/cartons.
There have some assumptions been made here:
A shipment has only one shipping method, even if it is shipped in several packages (cartons). They also share the same tracking number. Carriers usually group multiple cartons under the same tracking number. If a store handles this differently there is still a programmatic way to store a tracking number on a carton and it will still be displayed.
These assumptions have been made under the impression, that if stores have other fulfillment then Solidus default backend can provide, they will most likely have overwritten this view anyway.
Multiple cartons

Shipped split shipment

partially shipped

Split ready shipment

ready order

Shipped order

Checklist:
- [ ] I have followed Pull Request guidelines
- [ ] I have added a detailed description into each commit message
- [ ] I have updated Guides and README accordingly to this change (if needed)
- [ ] I have added tests to cover this change (if needed)
- [ ] I have attached screenshots to this PR for visual changes (if needed)