fix: set job's backoffLimit to 0 and report job's active/ready status in workspace

[Fei-Guo]

For Job workload, the backoffLimit specifies the number of retries before marking this job failed. Defaults to 6. In Kaito finetuning, there are not many benefits to recreate pods 6 times if the tuning fails, because the failures usually require user interventions.

This change also reports the job's ready pod count in workspace CR so that users do not need to frequently check the job object for status check. When tuning job is working, the ready count is 1. If the tuning container completes but the docker sidecar containers fails with infinite retry, the ready count becomes 0.

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