fix(cap-01): skip capacity gate for object-storage destinations

[gaikwadabhishek]

• CAP-01 ran statvfs on the destination → E401 "cannot determine free space" on s3:// targets
• _capacity_gate_destination() now returns None for object storage (s3/s3_torch)
• _pre_execution_gate then skips the gate via its existing remote-backend escape hatch
• local/direct_fs runs unchanged

[github-actions]

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[gaikwadabhishek]

I have mentioned my github username in my MLCommons profile. Where can I access the CLA form?

[gaikwadabhishek]

already fixed in main