Support for Block and Item Display

[dhouck]

Is your feature request related to a problem? Please describe.
Item and block display entities often seem like they should emit light, but they donʼt have hand or armor slots so you canʼt just give them something glowing.

Describe the solution you'd like
Block and item display entities should emit light appropriate for the block or item they are displaying.

Describe alternatives you've considered
A more general NBT tag for all entities to override dynamic light would also solve this problem in particular, but seems like it should be a separate feature; technically that can solve all problems with various entities, but display entities should still by default emit appropriate light.

Additional context
Add any other context or screenshots about the feature request here.