Fix 期期 sheets bias: split total 2n from same-sheets, not n.

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

tests/test_hedge_plan_calc.py

@@ -173,7 +173,7 @@ class TestHedgePlanCalc(unittest.TestCase):
         self.assertTrue(s["ok"])
 
     def test_suggest_oo_short_bias_sheets(self):
-        # same n=5; short → put major 4 / call minor 1 (round 5*0.7=4)
+        # 同张数 n=5 → 总张数 10; short → put 7 / call 3
         s = suggest_oo_sheets(
             mode="short_bias",
             budget_usdc=10,
@@ -187,8 +187,8 @@ class TestHedgePlanCalc(unittest.TestCase):
             bias_ratio=0.7,
         )
         self.assertEqual(s["mode"], "short_bias")
-        self.assertEqual(s["sheets_a"], 1)
-        self.assertEqual(s["sheets_b"], 4)
+        self.assertEqual(s["sheets_a"], 3)
+        self.assertEqual(s["sheets_b"], 7)
 
     def test_suggest_oo_bias_requires_call_put(self):
         s = suggest_oo_sheets(