Transport improvements for 2024-W36

[khaeru]

• Postprocess SSP 2024 reporting output to compute aviation emissions.
  • Initial implementation using a fixed share of total transportation emissions.
  • Compute absolute emissions using:
    • Emission factors from GAINS, at the highest possible resolution.
    • Aviation share of total transport final energy, computed using latest IEA EWEB data.
• Add transport mode F RAIL with two technologies.
• Add a technology for F ROAD that consumes commodity=electr.
• Add "SSP1-LED", "SSP2-LED", "EDITS-CA", "EDITS-HA" scenarios to transport workflow.
• Handle flow=AVBUNK in IEA EWEB data #229
• Handle missing countries in IEA EWEB data #230

Housekeeping:

• Add a emission code list.

How to review

• Read the diff and note that the CI checks all pass.
• View the preview build of the docs.
• Run the command described here and confirm (a) it works and (b) the output is as desired.

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 59.5%. Comparing base (7c50871) to head (9dc84fe).
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   59.5%   59.5%           
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  Files        195     195           
  Lines      15491   15491           
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  Hits        9225    9225           
  Misses      6266    6266