List Entry Mod Value GraphQL API

[pedro-gutierrez]

Is your feature request related to a problem? Please describe.

At the moment, we have GraphQL apis that manage both Needs and Available lists and entries.

We need to be able to attach existing mod values to those entries

Describe the solution you'd like

New GraphQL types and mutations that allow us to:

• Add an existing ModValue to an existing Needs or Available List Entry.
• Remove an existing ModValue attached to an existing list entry.

The GraphQL API must verify the following constraints:

• Only the mod values that are defined for the mods of the item can be selected.
• Either one or more mod values can be added to the entry, depending on the kind of Mod (integer, select or multi-select).

We will need an extra aid__list_entries__mod_values table that links existing mod_values to existing entries.