[#73104] Add Sprint column to work package table

[EinLama]

Ticket

https://community.openproject.org/wp/73104

What are you trying to accomplish?

Allows you to select the sprint column within the work package table and sort and group it.

Requires the view_sprints permission in a project to be available.

Screenshots

What approach did you choose and why?

There are some notable points here:

• Sorting uses the sprint name (as this is what the user sees in the work packages table). After that, sprints of the same name are sorted via start and finish dates.
• Added the ability for models to provide an API resource link name (commit 5014766). A resource link is necessary to make grouping work. The previous implementation added a manual mapping for some classes. Agile::Sprint would be converted to agile_sprint, but sprint is correct. So we have to add a mapping. Since the core should not be required to know about the backlogs module, I added a way for models to provide their API resource link name. The given name will be used by the mapping if available.
• To make the GROUP BY statement consider the view_sprints permission, a custom join was necessary - I think. The solution is similar to Implementation/62982 project phase column on work package list #18851, although this might be a case of "if I have a hammer, every problem looks like a nail". On the upside, this solution can be easily extended to work with further visibility checks in the future 👍

Merge checklist

• Added/updated tests
• Added/updated documentation in Lookbook (patterns, previews, etc)
• Tested major browsers (Chrome, Firefox, Edge, ...)
• Tested that the PDF export still works with sprints listed (and grouped by sprints)