Add docs pages for 2025 projects

[khaeru]

This PR adds docs pages for fifteen (15) projects mentioned in the 2025-01 projects overview (internal link) that were not so far mentioned anywhere in the MESSAGEix(-GLOBIOM) documentation.

We could expand this PR to:

• Update CODEOWNERS making the designated LM of the respective project the owner of the documentation page.
• Accept direct commits or PRs into this branch to populate the pages, all currently empty. This could be, initially, a transcription of the slide contents. Postponed to later PRs.

How to review

• View the preview build of the docs and confirm the project title is spelled and capitalized correctly.

PR checklist

• Continuous integration checks all ✅
• Add or expand tests; coverage checks both ✅
• Add, expand, or update documentation.
• Update doc/whatsnew.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.1%. Comparing base (91d6302) to head (d120fdd).
Report is 824 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #282     +/-   ##
=======================================
- Coverage   78.0%   77.1%   -0.9%     
=======================================
  Files        215     215             
  Lines      16572   16572             
=======================================
- Hits       12927   12779    -148     
- Misses      3645    3793    +148     

see 7 files with indirect coverage changes

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[khaeru]

@glatterf42 this is ready for review when you have a moment.

[glatterf42]

Thanks, this looks good to me :)

As an acronym connoisseur myself, I'd criticise the GENIE people because with their current spelling, it should be "GENIEE". Alternatively, the spelling should likely be "GeoEngineering and NegatIve emissions pathways in Europe​", which might set the wrong focus. But this seems besides the point 😅