[YangFei1990]

• I, the PR author, have personally reviewed every line of this PR.

What does this PR do?

This PR adds options to specify dtype for dispatch forward and combine backward (which is also a dispatch op). Currently it only supports bf16 and MXFP8

Note: the contract with TE is temporary, supported by this PR NVIDIA/TransformerEngine#3355. It allows to let TE return plain torch tensor, so mcore side does not require any special handling. In the future we will return grouped tensor, but make it compatible with mcore code path.

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