[WIP] Scan support

[JacobSzwejbka]

Add support for higher order ops scan. Its inefficient today because we are manually deep copying from output to input for every carry. We could do better by shallow swapping the pointers but Ill do that in a follow up if needed.

Test plan: Unit tests and internal verification against harder patterns

[pytorch-bot]

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❌ 2 New Failures

As of commit d563028 with merge base 5e96b43 ():

NEW FAILURES - The following jobs have failed:

• Lint / lintrunner / linux-job (gh)
  >>> Lint for exir/capture/_unlift.py:
• pull / unittest / macos / macos-job (gh)
  export/tests/test_target_recipes.py::TestTargetRecipes::test_mv3_model

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[meta-codesync]

@JacobSzwejbka has imported this pull request. If you are a Meta employee, you can view this in D88107948.