Multiple radiation bug fixes spotted by Claude

[mpaiao]

Description

This is a series of fixes to bugs identified by Claude as @xiangtaoxu was working on it ED2 two-stream RT bugs.

Most are not severe, but one could be important when optical properties vary across PFTs.

1. There is a PFT assignment issue for diffuse irradiance, but the code was not updating the pft index.

Collaborators

@xiangtaoxu

Types of changes

• Hot fix (emergential bug fix to make ED2 run again)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Other (fix or feature that would cause existing functionality to change)

Changes in Settings, Input Files or Output Files

• This feature requires changes in ED2IN
• This feature requires changes in the XML parameter file
• This feature requires changes in other input files
• This feature will change output files

Expectation of Answer Changes:

• No changes expected (bit-for-bit compatibility)
• Changes expected with specific configurations (see details below)
• [] Changes expected in all simulations (see details below)

Changes expected in any simulation in which PFTs have different optical properties.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• ED2 Wiki update:

Testing :

• All new and existing tests passed.