Libtorch 2.5.1

[dfalbel]

Add support for LibTorch 2.5.1

TODO:

• [x] Update Libtorch M1 builds - and patch the allocator
• [x] Regenerate R level wrappers
• [x] Figure out pre-built binaries for x86_64 macOS
• [x] Drop unsupported CUDA from CI
• [x] Figure out Windows build issues
• [x] Support CUDA 12.4
• [x] Fix crashes related to optional values
• [x] Fix loading of GenericDicts
• [x] Figure out windows deadlocks. Probably related to cleaning up the event loop.
• [x] Figure out failing tests on CUDA:

  -- Failure ('test-distributions-constraints.R:17:3'): positive definite --------
  as_array(object$cpu()) not equal to `expected`.
  10 element mismatches
  Backtrace:
      x
   1. \-torch:::expect_equal_to_r(...) at test-distributions-constraints.R:17:3
   2.   \-testthat::expect_equal(as_array(object$cpu()), expected, ...) at tests/testthat/helper-tensor.R:44:3