Create modular function to generate selectivity curves from ecosystem model maturity-at-age values by functional group

[Bai-Li-NOAA]

Description

Currently, the EwE model input specifies maturity-at-age by functional group. To integrate EwE input into FIMS, we need to 1) read maturity-at-age from EwE, 2) treat these as observations of logistic selectivity curve, and 3) estimate the underlying selectivity parameters that would reproduce that curve. We will have helper function such as fit_logistic_selectivity() from PR NOAA-FIMS/ecosystemdata#15 and we will need a high-level function that takes EwE input and return a FIMS-ready parameter tibble that can be used as initial values in estimation models. The expected output format:

model_family	module_name	fleet_name	module_type	label	distribution_link	age	length	time	value	estimation_type	distribution_type	distribution
catch_at_age	Maturity	NA	Logistic	inflection_point	NA	NA	NA	NA	2	constant	NA	NA
catch_at_age	Maturity	NA	Logistic	slope	NA	NA	NA	NA	1	constant	NA	NA

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