Allow n-band radiative transfer

[Espeer5]

Purpose

This PR extends our radiative transfer functionality from 2 bands (PAR and NIR) to an n-band scheme. This will allow pairing with ClimaAtmos which provides 16 bands. Represents step one towards #876.

This PR must be a large number of lines due to updating of all of the experiments and tests.

To-do

• Update fundamental radiation structs
• Update radiative transfer computations in models
• Repair all experiments and tests to work with new scheme
• Add a test for using up to 16 bands of radiation
• Check benchmarks and long runs to ensure no significant regressions
• Verify GPU compatibility is not broken

Content

• Adds a tuple-based type for the discretization of the λ spectrum
• All leaf & soil optics types are converted to tuple-valued fields
• Uses solar irradiance curve to allocate incoming shortwave to radiation bands
  • Also to compute PAR quantities from spectral absorption for photosynthesis
• Updates all tests and experiments to work with new structs / types

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• I have read and checked the items on the review checklist.