A target forward's post-final-norm hidden and, when the drafter taps layers, the tapped layers concatenated on the feature axis [B, L, m*H] (null otherwise). Both belong to the caller.
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A target forward's post-final-norm hidden and, when the drafter taps layers, the tapped layers concatenated on the feature axis [B, L, m*H] (null otherwise). Both belong to the caller.