Add copy-pr-bot config + performance smoke workflow

[fatimaanes]

Enables the OmniPerf performance-regression CI gate on NVKS RTX PRO 6000 runners via the copy-pr-bot push-trigger model (ProdSec forbids pull_request triggers on the self-hosted fleet).

Description

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (existing functionality will not work without user modification)
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