Function extract_soa 

pub fn extract_soa<A, S>(store: &S) -> (Vec<AgentId>, Vec<Vec<f32>>)
where
    A: SoaExtractable,
    S: AgentStore<A>,

Extract SoA buffers from an AgentStore.

Returns (ids, columns) where:

• ids[i] is the AgentId for row i
• columns[c][i] is column c for agent i