[FEATURE] Auto reload model when cluster rebooted/node rejoin

[ylwu-amzn]

Is your feature request related to a problem?
Refer to https://forum.opensearch.org/t/feedback-machine-learning-model-serving-framework-experimental-release/11439/19

I have noticed that models are not automatically loaded when the OpenSearch cluster is rebooted. Is there a way to do that? It would be impractical to manually reload models each time the cluster is rebooted, especially in a containerized setup.

What solution would you like?
We track each model's state in model index. When node restarted/rejoin cluster, check model state and reload model on corresponding ML node.

What alternatives have you considered?
NO

Do you have any additional context?
N/A