EntityIndexInQuery for systems (multithreaded more importantly)

Describe the problem you are trying to solve. I've been trying for a while to write data from a multithreaded system into a vector. With other ecs systems (mainly unity) I can simply grab the EntityIndexInQuery and use that with a ParallelWriter or directly into a NativeArray sized to match the query which works great and avoids locks. Initially I thought the index in the system provided with the flecs::iter was that but I noticed race conditions and empty fields, after looking into it found that the index isn't the entity index in the query which prevents me from writing into a vector without locks.

Describe the solution you'd like I would love if there was a simple way to get an index that you can use for writing data without a lock, like it.entity_index_in_query(i). Or anything similar to this.

And if there is actually a way to do this or a different approach I can try I would love to try it