weights
The count-weighted mean of all peer contributions, per coordinate.
Computed as Σ_k(n_k · w_k[i]) / Σ_k(n_k) for each coordinate i. Sums are evaluated in canonical ReplicaId order (lexicographic) for bit-for-bit reproducibility across replicas and platforms.
Throws
if no peer has contributed (total sample count is zero), or if peers contributed weight vectors of differing dimension (the FedAvg contract requires the same dimension across all peers — a mismatch would silently skew the mean toward zero via padding, so fail loud instead).