Add eval name to prime eval push if set

[xeophon]

The PR adds the eval name from the metadata to the eval push if it was set by the user

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Note

Low Risk
Low risk: small change limited to naming derived from metadata.json, with no changes to API calls or data processing beyond selecting the eval display name.

Overview
When loading a local eval directory, the CLI now prefers an explicit eval name from metadata.json (via eval_name or name) instead of always generating "<env>-<model>".

If the provided name is missing/empty/non-string, it falls back to the previous default generated name.

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