Bugfix SCP "mixed" scenario + "kfo_rd" set added to config file

[flohump]

Please fill following information
(Add additional info if you think its important and not covered by this Pull Request (PR)):

Purpose of this PR

• The "mixed" scenario for single-cell protein production (c20_scp_type) was not working as expected. The corresponding code in 20_processing has been updated. Review needed from @bodirsky
• The set "kfo_rd" (livst_rum, livst_milk), which is used in the food substitution scenarios c15_rumdairy_scp_scen and c15_rumdairyscen, has been added to the default.cfg file. This allows for sensitivity scenarios (e.g. only livst_milk or only livst_rum). Review needed from @weindl

Performance loss/gain from current default behavior

• Add an image using plot from shinyresults::appResults() and annotate accordingly.

Both scenarios reflecting a default model run (based on default.cfg)
SCP34 = current develop
SCP35 = f_SCP2
The run time is almost the same (slightly faster).

• %performance loss/gain = 100*Runtime from PR/Runtime from current default from develop branch.

Type of change

• Bug fix (Change which fixes an issue).
• New feature (Change which adds functionality).
• Minor change (Change which does not modify core model code i.e., in /modules).
• Major change (fix or feature that would change current model behavior).

How Has This Been Tested?

• Runs using starting script paper_scp.R

Additions or Changes to default configuration (default.cfg):

Additions are the introduction of new model components in default config

Changes are deletion or updates to the existing model components in default config

• Realizations:
• Scenario switches: cfg$gms$c20_scp_type <- "sugar" (change), cfg$gms$kfo_rd <- "livst_rum,livst_milk" (addition)
• Scalars/Constants:
• Model interfaces:
• Others:

Checklist:

• Self-review of my own code.
• Compilation check (model starts without compilation errors).
• Added changes to CHANGELOG.md
• No hard coded numbers and cluster/country/region names.
• The code doesn't contain declared but unused parameters or variables.
• In-code comments added including documentation comments.
• Compiled and checked resulting documentation with goxygen::goxygen() for the new/updated parts.
• Changes to magpie4 R library for post processing of model output (ideally backward compatible).

Special comments/warnings

• Notes

[tscheypidi]

why do you need $onMultiR here?

[flohump]

Because the set kfo_rd needs to be defined in sets.gms (some declarations depend on kfo_rd) and then overwritten in input.gms.

[flohump]

@bodirsky @weindl @tscheypidi I need your feedback on this PR.

[tscheypidi]

looks good to me, but could you please pull the recent version of develop into your branch as there was recently another PR accepted (I don't see these changes in your diff view at the moment for some reason)

[flohump]

looks good to me, but could you please pull the recent version of develop into your branch as there was recently another PR accepted (I don't see these changes in your diff view at the moment for some reason)

Done!

[bodirsky]

a few tiny changes (see comments above)