Fix payroll tax revenue double-counted in aggregates.revenue (Issue #1199)

[arihantlodha-cmd]

Fixes #1199. Thanks @marcelolafleur for the precise diagnosis — this is a regression I introduced in #1184, so cleaning it up.

The bug. Each household's income_payroll_tax_liab already includes T_P = tau_payroll * labor_income (in tax.income_tax_liab), so payroll revenue is fully inside iit_payroll_tax_revenue. In #1184 I then added get_payroll_tax_revenue — the same take, re-derived from the aggregate wage bill tau_payroll * w * L — back into that same total whenever tau_payroll != 0. The two are the same money, so revenue was overstated by the payroll take, the government spent it, and the steady-state resource constraint failed. Any model with a nonzero tau_payroll broke (OG-PHL); OG-USA was unaffected only because its tau_payroll is 0.

The fix. Remove the erroneous if np.any(p.tau_payroll != 0): iit_payroll_tax_revenue += payroll_tax_revenue. iit_payroll_tax_revenue stays what the line above builds (household bills, payroll already inside). get_payroll_tax_revenue is kept — it still provides the income-vs-payroll reporting split (iit_revenue = iit_payroll_tax_revenue - payroll_tax_revenue), which is the genuinely useful part of #1184 and is unchanged.

I also restored the test_revenue golden values, which #1184 had inflated to match the double-count. I pulled them from the commit just before #1184's second commit and confirmed they are identical, so this returns the totals to exactly the pre-#1184 (correct) amounts.

Testing

• pytest tests/test_aggregates.py → 43 passed; test_revenue (including the tau_payroll = 0.5 cases) and test_get_payroll_tax_revenue both green.
• ruff format --check . / ruff check . clean.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.73%. Comparing base (2b6a668) to head (4160653).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1204      +/-   ##
==========================================
- Coverage   72.74%   72.73%   -0.01%     
==========================================
  Files          22       22              
  Lines        5768     5766       -2     
==========================================
- Hits         4196     4194       -2     
  Misses       1572     1572              

Flag	Coverage Δ
unittests	72.73% <ø> (-0.01%)	⬇️

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Files with missing lines	Coverage Δ
ogcore/aggregates.py	100.00% <ø> (ø)

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