Add MPS Pytorch support for batched_mask_to_box function

[GenevieveBuckley]

This PR adds an edited copy of the batched_mask_to_box() function from segment_anything/utils/amg.py to the micro-sam codebase. The function has been edited to solve two problems:

1. It makes this function compatible with the MPS PyTorch backend for apple silicon, and
2. We add a check that the input mask dtype is boolean (since apparently there is some bug that means masks with integer dtypes return completely different results 👀 )

The license for segment-anything is Apache 2.0, which is compatible with the MIT licence micro-sam uses.

Eventually, if this gets fixed upstream we can remove it from the micro-sam code and go back to using the batched_mask_to_box() function directly from segment-anything. But that seems unlikely to happen soon.

• Currently there is a PR open for adding MPS support, but there has been no activity since June 2023
  Added changes for MPS facebookresearch/segment-anything#122
• As far as I know, no one has reported the bug involving boolean vs integer mask input to batched_mask_to_box(). Creating an issue would be helpful here (maybe I'll try and do that this evening).

Extra context: discussed here previously on the main PR for adding .MPS support to micro-sam.

[GenevieveBuckley]

Update: I did make an issue facebookresearch/segment-anything#552

[constantinpape]

Thanks for all this @GenevieveBuckley, and also for finding the relevant PRs in SAM. I agree with your strategy: let's see if they fix these issues on the SegmentAnything side and until then we keep the vendored function.
And it's a pity that they stopped engaging with the community on the repo... I will think about if there's some way to reach out to the authors and ask if there's a possibility to look into these issues.