Function ships_vanilla_norm_weights 

pub fn ships_vanilla_norm_weights(config: &ModelConfig) -> bool

2026-09-26: True when the checkpoint’s RMSNorm weights are plain multipliers, out = x * w / rms (the rms_norm_vanilla kernel), rather than offsets from 1, out = x * (1 + w) / rms (the rms_norm kernel). It selects the final-norm kernel (model-engine model/impl_a1.rs) and the attention norm kernels (layers/qwen3_attention/init_proj_kernels.rs and init_prefill_kernels.rs). The answer comes from model_type alone, not from the weight values.