fix: upgrade django-simple-history 3.0.0 -> 3.7.0

[devinbarry]

Summary

• Upgrades django-simple-history from 3.0.0 to 3.7.0 to fix pkg_resources ModuleNotFoundError during collectstatic (build STEP 11/17)
• Version 3.0.0 imports pkg_resources at runtime, which was removed in setuptools>=82. Version 3.7.0 uses pyproject.toml/Hatchling instead, eliminating the dependency
• Updated all 4 requirement files (requirements.in, requirements.txt, requirements-dev.in, requirements-dev.txt)

Compatibility

• 3.7.0 requires Django >= 4.2 (project uses 5.0.14) and Python >= 3.8 (project uses 3.12)
• No breaking API changes; project uses only basic HistoricalRecords() on 5 models + middleware

Test plan

• Full local test suite passes (1442 passed, 78 skipped)
• CI pipeline passes (build STEP 11/17 collectstatic no longer fails)

[devinbarry]

Build is green again