pytorch

4b945967 - [dtensor] PART 2: move DTensor abstraction and APIs to core distributed (#88176)

[dtensor] PART 2: move DTensor abstraction and APIs to core distributed (#88176) This PR moves the core DTensor abstraction and high level APIs to torch.distributed._tensor folder, which includes the following: 1. DTensor class 2. high level APIs (distribute_tensor/module) 3. dispatching logic 4. redistribute logic part of https://github.com/pytorch/pytorch/issues/88838 Pull Request resolved: https://github.com/pytorch/pytorch/pull/88176 Approved by: https://github.com/fduwjj