Get Referral Weights

Epoch-stable public feed of each referrer's referral EMA keyed by SN51 hotkey.

A subnet validator polls this endpoint and pays the EMA through mining emission. The EMA values only change when the accrue task folds a new epoch (advancing ReferralFoldState.last_processed_epoch), so the fully-serialized response is cached in Redis under a key that includes that watermark. Two reads within the same fold-epoch return byte-identical bodies, and the watermark and weights can never straddle a fold commit (see :func:_build_referral_weights_body).