Unity ECS Integration

[zaucy]

we may be able to integrate a little bit with Unity's ECS: https://unity.com/ecs

Some Ideas

• C# codegen could have all Ecsact components implement IComponentData
• codegen for some boilerplate readonly access to Ecsact components to use for local visual only changes
• keep a duplicate set of entities in Unity DOTS for quick access and more seamless
  • a duplicate set of entities would also allow developer to write to existing Ecsact components with the caveat of Ecsact components eventually being overwritten by runtime events.

What we won't do

• Use the C# job system for Ecsact system implementations. Ecsact's system implementations are not compatible with Unity's C# jobs. Ecsact already handles system execution. This is important for Ecsact to do because these systems also run on a server to keep the simulation deterministic with the server and the client. Instead the job systems could be used for visual parts of gameplay such as particles or interpolation.