fix player win % and visual overhaul

tests/test_stats.py

@@ -5,6 +5,42 @@ from boker.services import build_leaderboard
 
 
 class CashInAccountingTest(unittest.TestCase):
+    def test_leaderboard_win_pct_is_percent_not_ratio(self):
+        sessions = [
+            SessionSummary(
+                session_id="2026-06-21-01",
+                session_date="2026-06-21",
+                entries=[
+                    SessionEntry(
+                        session_id="2026-06-21-01",
+                        session_date="2026-06-21",
+                        player_name="Alex",
+                        buy_in_cents=1000,
+                        cash_out_cents=1500,
+                    )
+                ],
+            ),
+            SessionSummary(
+                session_id="2026-06-28-01",
+                session_date="2026-06-28",
+                entries=[
+                    SessionEntry(
+                        session_id="2026-06-28-01",
+                        session_date="2026-06-28",
+                        player_name="Alex",
+                        buy_in_cents=1000,
+                        cash_out_cents=0,
+                    )
+                ],
+            ),
+        ]
+
+        player = build_leaderboard(sessions)[0]
+
+        self.assertEqual(player.winning_sessions, 1)
+        self.assertEqual(player.sessions_played, 2)
+        self.assertEqual(player.win_pct, 50.0)
+
     def test_front_is_poker_investment_not_cash_in(self):
         entry = SessionEntry(
             session_id="2026-06-21-01",