Stage 6.1: CRA staking pool, SPARK balance token with mint/burn

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

src/Decentralized/Session.cs

@@ -29,6 +29,10 @@ namespace Decentralized
         public Rng Rng = new Rng((ulong)DateTime.UtcNow.Ticks);
         public Market Market;
         public Stablecoins Stable = new Stablecoins();
+        /// <summary>革命军 CRA 质押池里玩家各钱包的仓位。</summary>
+        public Staking Staking = new Staking();
+        /// <summary>质押日息下调的新闻已经发过。</summary>
+        public bool CraLowNews;
         public Network Network = new Network();
         /// <summary>链上钱包（硬件钱包，第一个是主钱包），各自的余额、污点、成本、冻结独立。</summary>
         public List<Wallet> Wallets = new List<Wallet>();
@@ -125,6 +129,7 @@ namespace Decentralized
             if (asset == Assets.PSC) return Data.Market.Price;
             var spec = Assets.Get(asset);
             if (asset == Assets.Ponero) return BlackMarket.PoneroPrice(Data.Market.Price);
+            if (asset == Assets.SPARK) return Data.Stable.Spark;
             if (spec != null && spec.Stable) return Data.Stable.Price(asset);
             return 0;
         }