feat(CORE-001B): migrate overview and hedge math to unit types

tests/test_e2e_playwright.py

@@ -193,8 +193,12 @@ def test_homepage_and_options_page_render() -> None:
         assert "$222,000" in hedge_text
         assert "80.0%" in hedge_text
         assert "$12,345" in hedge_text
+        assert "Scenario spot" in hedge_text
+        assert "$3,520.00" in hedge_text
         assert "Unhedged equity" in hedge_text
+        assert "$552,400" in hedge_text
         assert "Hedged equity" in hedge_text
+        assert "$551,025" in hedge_text
         page.screenshot(path=str(ARTIFACTS / "hedge.png"), full_page=True)
 
         browser.close()

tests/test_portfolio_math.py

@@ -0,0 +1,67 @@
+from __future__ import annotations
+
+from app.domain.portfolio_math import (
+    build_alert_context,
+    portfolio_snapshot_from_config,
+    strategy_metrics_from_snapshot,
+)
+from app.models.portfolio import PortfolioConfig
+from app.pages.common import strategy_catalog
+
+
+def test_portfolio_snapshot_from_config_preserves_weight_price_and_margin_values() -> None:
+    config = PortfolioConfig(entry_price=4400.0, gold_ounces=220.0, entry_basis_mode="weight", loan_amount=145000.0)
+
+    snapshot = portfolio_snapshot_from_config(config)
+
+    assert snapshot["spot_price"] == 4400.0
+    assert snapshot["gold_units"] == 220.0
+    assert snapshot["gold_value"] == 968000.0
+    assert snapshot["net_equity"] == 823000.0
+    assert round(snapshot["margin_call_price"], 2) == 878.79
+
+
+def test_build_alert_context_uses_unit_safe_gold_value_calculation() -> None:
+    config = PortfolioConfig(entry_price=4400.0, gold_ounces=220.0, entry_basis_mode="weight", loan_amount=145000.0)
+
+    context = build_alert_context(
+        config,
+        spot_price=4400.0,
+        source="configured_entry_price",
+        updated_at="",
+    )
+
+    assert context["gold_units"] == 220.0
+    assert context["gold_value"] == 968000.0
+    assert context["net_equity"] == 823000.0
+    assert round(float(context["margin_call_price"]), 2) == 878.79
+
+
+def test_strategy_metrics_from_snapshot_preserves_minus_20pct_protective_put_example() -> None:
+    strategy = next(item for item in strategy_catalog() if item["name"] == "protective_put_atm")
+    snapshot = {
+        "gold_value": 215000.0,
+        "loan_amount": 145000.0,
+        "net_equity": 70000.0,
+        "spot_price": 215.0,
+        "gold_units": 1000.0,
+        "margin_call_ltv": 0.75,
+        "margin_call_price": 193.33,
+        "cash_buffer": 18500.0,
+        "hedge_budget": 8000.0,
+        "ltv_ratio": 145000.0 / 215000.0,
+    }
+
+    metrics = strategy_metrics_from_snapshot(strategy, -20, snapshot)
+
+    assert metrics["scenario_price"] == 172.0
+    assert metrics["unhedged_equity"] == 27000.0
+    assert metrics["hedged_equity"] == 58750.0
+    assert metrics["waterfall_steps"] == [
+        ("Base equity", 70000.0),
+        ("Spot move", -43000.0),
+        ("Option payoff", 38000.0),
+        ("Call cap", 0.0),
+        ("Hedge cost", -6250.0),
+        ("Net equity", 58750.0),
+    ]