[Serve][UX] Fine-grained reason for a replica failure

[cblmemo]

Currently our recommendation to users is to check logs if the replica fails, but it might be easier to understand/debug if we can clearly state in the sky status output.

Potential solutions:

• More replica status, e.g. RUN_FAILED, SETUP_FAILED;
• Add a column to indicate failure reason in a plain text string.

[brian316]

you can run sky serve logs <service_name> <replica_id> to see the logs of the failing replica, but i agree that skypilot should have a status for failed build or stop creating new replicas if a max number of attempts was made

[cblmemo]

Already resolved by #3411. Closing now