[Profiler] Add dtype to `_TensorMetadata` (#85721)
`Inputs.dtypes_` stringifies the dtypes; however this loses information which is hard to recover and useful for analysis. So this PR adds full `torch.dtype` info for Tensors.
Differential Revision: [D39852802](https://our.internmc.facebook.com/intern/diff/D39852802/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85721
Approved by: https://github.com/chaekit
