Ensure balance is set for shipped/piped comms

[junukitashepard]

Ensure that balance equality is set for shipped and piped level traded commodities.

This, in combination with updated historical activity for imports, ensures that bilaterally traded commodities are balanced.

How to review

• Read the diff and note that the CI checks all pass.

PR checklist

• Continuous integration checks all ✅
• Existing tests cover patch ✅

[codecov]

Codecov Report

❌ Patch coverage is 6.25000% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 69.4%. Comparing base (54fe267) to head (b165c82).

Files with missing lines	Patch %	Lines
...age_ix_models/tools/bilateralize/load_and_solve.py	6.2%	15 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #481     +/-   ##
=======================================
- Coverage   69.5%   69.4%   -0.1%     
=======================================
  Files        300     300             
  Lines      24598   24614     +16     
=======================================
  Hits       17104   17104             
- Misses      7494    7510     +16     

Files with missing lines	Coverage Δ
...age_ix_models/tools/bilateralize/load_and_solve.py	53.1% <6.2%> (-4.8%)	⬇️

... and 1 file with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.