Link `get_observed` and `get_expected` to different parameters/derived quantities in the model

[e-perl-NOAA]

Describe the problem, idea, or request that you have and, if possible, provide a solution.

This will happen in the information.hpp file similar to SetupData() and will need a info->variable_map in rcpp_dsem.hpp - this will be harder to do because we have to link up the x vector with multiple parameters and how to get the ordering correct for this.

Additional context

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Which OS are you seeing the problem on?

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Which version of this package are you seeing the problem on?

No response