fix(ledger): split dividend response schema and harden decimal tests

Co-authored-by: genichin <4282227+genichin@users.noreply.github.com>

tests/test_bat025_portfolio_ledger_manual_metadata_migration.py

@@ -292,7 +292,7 @@ def test_dividend_precision_and_reversal_round_trip_on_real_postgres(
 
     assert dividend.price == 0.00000001
     assert dividend.tax_amount == 0.00000001
-    assert str(dividend.tax_amount_decimal) == "0.00000001"
+    assert dividend.tax_amount_decimal == Decimal("0.00000001")
     assert dividend.profit_buffer_after == 0.00000001
     with repo._connect().cursor() as cur:
         cur.execute(
@@ -330,7 +330,7 @@ def test_dividend_tax_omitted_persists_zero_on_real_postgres(
         note="tax-omitted",
     )
     assert dividend.tax_amount == 0.0
-    assert str(dividend.tax_amount_decimal) == "0E-8"
+    assert dividend.tax_amount_decimal == Decimal("0.00000000")
     with repo._connect().cursor() as cur:
         cur.execute("SELECT tax_amount::text FROM portfolio_ledger WHERE ledger_entry_id = %s", (dividend.ledger_entry_id,))
         assert cur.fetchone()[0] == "0.00000000"
@@ -431,7 +431,7 @@ def test_large_invest_and_large_dividend_tax_metadata_are_accepted_when_snapshot
         note="large-tax-metadata",
     )
     assert dividend.tax_amount == 50000000.0
-    assert str(dividend.tax_amount_decimal) == "50000000.00000000"
+    assert dividend.tax_amount_decimal == Decimal("50000000.00000000")
     repo.close()
 
 
@@ -458,8 +458,8 @@ def test_dividend_tax_alias_prone_decimals_round_trip_distinctly_on_real_postgre
         executed_at=datetime(2026, 9, 2, 0, 0, 0, tzinfo=UTC),
         note="alias-tax-2",
     )
-    assert str(first.tax_amount_decimal) == "90000000.00000001"
-    assert str(second.tax_amount_decimal) == "90000000.00000002"
+    assert first.tax_amount_decimal == Decimal("90000000.00000001")
+    assert second.tax_amount_decimal == Decimal("90000000.00000002")
     repo.close()
 
 

tests/test_v1_portfolios_manual_ledger.py

@@ -981,9 +981,12 @@ def test_unified_ledger_openapi_contains_nullable_amount() -> None:
     response = client.get("/openapi.json")
     assert response.status_code == 200
     schemas = response.json()["components"]["schemas"]
-    assert "amount" in schemas["LedgerHistoryItem"]["properties"]
-    amount_schema = schemas["ManualLedgerResponse"]["properties"]["amount"]
-    assert any(option.get("type") == "number" for option in amount_schema.get("anyOf", []))
+    manual_amount_types = {option.get("type") for option in schemas["ManualLedgerResponse"]["properties"]["amount"]["anyOf"]}
+    assert manual_amount_types == {"number", "null"}
+    assert schemas["DividendManualLedgerResponse"]["properties"]["amount"]["type"] == "string"
+    history_amount_types = {option.get("type") for option in schemas["LedgerHistoryItem"]["properties"]["amount"]["anyOf"]}
+    assert history_amount_types == {"number", "null"}
+    assert schemas["DividendLedgerHistoryItem"]["properties"]["amount"]["type"] == "string"
 
 
 def test_reversal_rejects_fee_tax_and_missing_target() -> None: