Skip np.transpose for identity dim_order in process_node

[mcremon-meta]

Summary:
When dim_order is the identity permutation (0, 1, ..., N-1),
np.transpose is a no-op that may create an unnecessary array copy.
Add an early return to avoid this.

Differential Revision: D101430550

[pytorch-bot]

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❌ 1 New Failure, 4 Unrelated Failures

As of commit 36b17b7 with merge base 4618b80 ():

NEW FAILURE - The following job has failed:

• Build Presets / linux (pybind, linux.2xlarge, executorch-ubuntu-22.04-clang12) / build (gh)

FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• pull / test-selective-build-linux / linux-job (gh) (detected as infra flaky with no log or failing log classifier)
• pull / test-static-llama-qnn-linux (stories_260k_bc) / linux-job (gh) (detected as infra flaky with no log or failing log classifier)

BROKEN TRUNK - The following jobs failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• pull / unittest / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / unittest-editable / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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[meta-codesync]

@mcremon-meta has exported this pull request. If you are a Meta employee, you can view the originating Diff in D101430550.

[github-actions]

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[mcremon-meta]

@AdrianLundell can I get a stamp here if it looks good?