fix(hub): show contract-based unrealized PnL in monitor and chart

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_hub_agent_mark_price.py

@@ -11,7 +11,11 @@ sys.path.insert(0, str(ROOT / "manual_trading_hub"))
 from agent import _position_mark_price, _ticker_mark_price  # noqa: E402
 
 sys.path.insert(0, str(ROOT))
-from hub_position_metrics import parse_position_unrealized_pnl  # noqa: E402
+from hub_position_metrics import (  # noqa: E402
+    estimate_linear_swap_upnl_usdt,
+    parse_position_unrealized_pnl,
+    resolve_position_display_upnl,
+)
 
 
 class TestHubAgentMarkPrice(unittest.TestCase):
@@ -48,6 +52,24 @@ class TestHubAgentMarkPrice(unittest.TestCase):
         )
         self.assertAlmostEqual(pnl, 6.81)
 
+    def test_estimate_short_hype_contract_size(self):
+        upnl = estimate_linear_swap_upnl_usdt(
+            "short", 73.187, 66.038, 11, 0.1
+        )
+        self.assertAlmostEqual(upnl, 7.86, places=1)
+
+    def test_resolve_prefers_computed_when_exchange_off(self):
+        shown = resolve_position_display_upnl(
+            "short", 73.187, 66.038, 11, 1.0, 7.86
+        )
+        self.assertAlmostEqual(shown, 78.64, places=1)
+
+    def test_resolve_keeps_exchange_when_aligned(self):
+        shown = resolve_position_display_upnl(
+            "short", 73.187, 66.038, 11, 0.1, 7.86
+        )
+        self.assertAlmostEqual(shown, 7.86, places=2)
+
 
 if __name__ == "__main__":
     unittest.main()