Investigate equivalent to babylon.js 'thin instance' functionality

[ProfLander]

• Similar to InstanceSlice; a contiguous block of instances that all draw together with no visibility culling
• Primary use case is wasm, needs a low-overhead solution to instancing in the absence of compute
• Use a variant of the regular component-based interface
  • Minus the ComputedVisibility?
• Ideally data should be updated on change to minimize overhead
  • This could benefit regular instances too