pkg: add expander for cloud secrets

[alenkacz]

This will allow us to implement expansion of secrets.

The MaybeExpand can be dropped later, once we switch to jan's new api. It's just for experimentation with passing in the interpolated value.

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[chrisseto]

LGTM!

However, the added imports (Looking at you OTEL) might cause some conflicts in the operator. Ahead of merging, would you mind trying to build the operator with this change? Just add a replace directive to the operators go.mod and run task build, that should let us know if there's any version conflicts we'll have to dance around.

In my experience most google libraries, proto libraries, and otel have a tendency to make dependency management very painful.

[jan-g]

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[alenkacz]

💚 All backports created successfully

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[jan-g]

💚 All backports created successfully

Status	Branch	Result
✅	release/v25.1.x

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Questions ?

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