Add option for MESSAGE-MAgPIE connection

[ywpratama]

Required: TBA Commits history is mixed with commits not intended to be included in this draft pull request. The list of what were done includes:

1. Create a draft pull request for the project/justmip_rebase_magpie branch
2. Rebase the draft PR against main
3. Resolve conflicts
4. Force push the rebase to the branch
5. Together with Paul, rebasing and cleaning up the branch to exclude unwanted commits
   • The branch history is now cleaned up
6. Yoga is currently identifying changes made to GAMS code and analysing potential approaches to add option to MAgPIE connection

How to review

Required: describe specific things that reviewer(s) must do, in order to ensure that the PR achieves its goal. If no review is required, write “No review:” and describe why.

PR checklist

• [ ] Continuous integration checks all ✅
• [ ] Add or expand tests; coverage checks both ✅
• [ ] Add, expand, or update documentation.
• [ ] Update release notes.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}