Support physical units for BOM lines

[SchrodingersGat]

• Closes [Feature] Support physical units for BOM lines #4922

This PR implements support for physical units in BOM items.

Tasks

• Data / schema migrations
• Update serializers and API endpoints
• Continue to allow write to "quantity" field (if "raw_amount" field not present)
• Logic for validating raw amount
• Update existing unit tests
• Additional unit tests for physical unit / quantity validation
• Additional playwright tests
• Update documentation
• Update CHANGELOG.md
• Perform data migration on demo dataset
• Add non-numeric raw-amount values to demo dataset (for testing)

[netlify]

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[codecov]

Codecov Report

❌ Patch coverage is 60.71429% with 22 lines in your changes missing coverage. Please review.
✅ Project coverage is 91.22%. Comparing base (366d4c3) to head (0e4cac4).

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #11631      +/-   ##
==========================================
- Coverage   91.35%   91.22%   -0.13%     
==========================================
  Files         967      968       +1     
  Lines       50242    50284      +42     
==========================================
- Hits        45897    45873      -24     
- Misses       4345     4411      +66     

Flag	Coverage Δ
backend	89.12% <60.71%> (-0.13%)	⬇️

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Components	Coverage Δ
Backend Apps	91.52% <60.71%> (-0.18%)	⬇️
Backend General	93.41% <ø> (ø)
Frontend	∅ <ø> (∅)

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