[refactor] Translate into english, void Chinese due to claude.

nanovllm/layers/layernorm.py

@@ -18,6 +18,8 @@ class RMSNorm(nn.Module):
         self,
         x: torch.Tensor,
     ) -> torch.Tensor:
+        # Input MUST be 2D [N, D] to avoid recompilation due to rank mismatch
+        # Callers should reshape 3D tensors to 2D before calling
         orig_dtype = x.dtype
         x = x.float()
         var = x.pow(2).mean(dim=-1, keepdim=True)
@@ -31,6 +33,7 @@ class RMSNorm(nn.Module):
         x: torch.Tensor,
         residual: torch.Tensor,
     ) -> tuple[torch.Tensor, torch.Tensor]:
+        # Input MUST be 2D [N, D] to avoid recompilation due to rank mismatch
         orig_dtype = x.dtype
         x = x.float().add_(residual.float())
         residual = x.to(orig_dtype)