[Profiler] Clean up Tensor representation (#85161)
I want to start using `TensorMetadata` elsewhere in profiler so we have a common representation of Tensor. The main changes in this PR are:
1) Replace raw pointers with strong typedefs and create a custom type caster to handle moving them to Python.
2) Adding a `device()` method to handle reassembling type and index.
Differential Revision: [D39563965](https://our.internmc.facebook.com/intern/diff/D39563965/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85161
Approved by: https://github.com/chaekit
