fix(dynamo): clone folded constants returned as graph outputs

[curry-zzl]

Description

Constant folding can replace input-independent tensor factories such as torch.zeros with registered _frozen_param* attributes. When one of these constants is returned directly across a graph break, eager code may mutate the returned tensor in-place. That mutation then changes the registered constant and leaks state into later top-level invocations.

This change extends repair_input_as_output to clone direct graph outputs backed by folded constants, preserving the registered constant while keeping constant folding enabled.

A regression test mutates the first returned tensor and verifies that both a subsequent output and the underlying _frozen_param remain unchanged.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented the non-obvious graph-break behavior
• I have added a test to verify the fix
• New and existing unit tests pass locally with my changes

Validation

• python -m py_compile passes for the modified pass and test.
• The focused pytest collection in the development container is blocked because the source checkout does not contain the generated torch_tensorrt._version module. The equivalent regression was validated in the installed runtime environment.

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