Enhance entry price logic in Maker and Liquidity Maker strategies

- Added `entryDepthLevel` configuration option to `MakerConfig` and `LiquidityMakerConfig` for specifying order entry levels.
- Implemented `getPricesAtLevel` utility function to retrieve bid and ask prices at specified depth levels.
- Updated `MakerEngine`, `LiquidityMakerEngine`, and `OffsetMakerEngine` to utilize the new entry level logic for determining opening prices based on market depth.
- Improved price handling to ensure more accurate order placements in varying market conditions.

src/utils/price.ts

@@ -9,6 +9,46 @@ export function getTopPrices(depth?: AsterDepth | null): { topBid: number | null
   };
 }
 
+/**
+ * 获取指定档位的盘口价格
+ * @param depth 深度数据
+ * @param level 档位（1=买1/卖1，2=买2/卖2，以此类推）
+ * @returns 指定档位的买卖价格，如果该档位不存在则回退到最近的有效档位
+ */
+export function getPricesAtLevel(
+  depth?: AsterDepth | null,
+  level: number = 1
+): { bidAtLevel: number | null; askAtLevel: number | null } {
+  const index = Math.max(0, level - 1);
+
+  // 尝试获取指定档位，如果不存在则回退到最近的有效档位
+  const bids = depth?.bids ?? [];
+  const asks = depth?.asks ?? [];
+
+  let bidAtLevel: number | null = null;
+  let askAtLevel: number | null = null;
+
+  // 从指定档位向前查找第一个有效的买价
+  for (let i = Math.min(index, bids.length - 1); i >= 0; i--) {
+    const bid = Number(bids[i]?.[0]);
+    if (Number.isFinite(bid)) {
+      bidAtLevel = bid;
+      break;
+    }
+  }
+
+  // 从指定档位向前查找第一个有效的卖价
+  for (let i = Math.min(index, asks.length - 1); i >= 0; i--) {
+    const ask = Number(asks[i]?.[0]);
+    if (Number.isFinite(ask)) {
+      askAtLevel = ask;
+      break;
+    }
+  }
+
+  return { bidAtLevel, askAtLevel };
+}
+
 export function getMidOrLast(depth?: AsterDepth | null, ticker?: AsterTicker | null): number | null {
   const { topBid, topAsk } = getTopPrices(depth);
   if (topBid != null && topAsk != null) return (topBid + topAsk) / 2;