## Summary
- net transfer categories in the cashflow Sankey on their configured
side instead of showing gross signed flows
- keep the existing mixed-sign behavior for non-transfer categories so
regular income and expense categories can still appear on both sides
- add regression coverage for zero-net inflow transfers and partial
inflow/outflow transfer netting
## Testing
- vendor/bin/pint --dirty --format agent
- php artisan test --compact tests/Feature/CashflowAnalyticsTest.php
--filter=sankey
## Notes
- running the full `CashflowAnalyticsTest` file in this workspace still
hits two unrelated page tests because `public/build/manifest.json` is
missing locally
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