Candles and volume for every traded asset, chart asset switcher

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/Decentralized.Domain/Candles.cs

@@ -65,6 +65,10 @@ namespace Decentralized.Domain
             Today(asset, day, price).Closed = true;
         }
 
+        /// <summary>NPC 当天的成交额（信用点）：基础量随池深，波动越大成交越多。</summary>
+        public static double NpcVolume(double depth, double share, double absMove, Rng rng) =>
+            depth * share * (1 + Tuning.ChartVolMove * absMove) * rng.Range(0.6, 1.4);
+
         /// <summary>收盘价的 n 日均线（不足 n 根时用已有的）；每根蜡烛一个值。</summary>
         public static List<double> Ma(IList<Candle> s, int n)
         {