Preserve hook forward signature

[jloftin-nv]

What does this PR do?

Fixes HookRegistry.register_hook breaking a module's forward signature, and downstream prevents torch.compile / torch.export - specifically affecting context parallel hooks

Fixes #14135

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Who can review?

@sayakpaul

[sayakpaul]

Should we ensure that the exported program can also execute?

[HuggingFaceDocBuilderDev]

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