[FEAT]: Add support for hidden nodes

[rd790-gh]

Proposal

Extend the MongoDB operator to include options for configuring hidden nodes.

Use-Case

We'd use the hidden nodes for running heavy read operations, such as generating reports or performing data analysis, without affecting the performance of the main replica set.

Is this a feature you are interested in implementing yourself?

Maybe

Anything else?

No response

[spron-in]

@rd790-gh thank you for sharing. We have non-voting nodes, I think implementing hidden would be quite similar to that one.

[kyeongjun-dev]

When there are a large number of documents in MongoDB, a new replica member may report an OK status to the client even though it has not fully synchronized all the data.

For instance, in a case with 500,000 documents, a read request from the client might be directed to the newly added replica member, and the response could return only 400,000 documents. Despite this, the client still receives an OK status.

This is based on a test I conducted, and from this experience, I believe adding the capability to configure a new replica member as hidden would be highly beneficial.