docs: enhance benchmark command with business logic validation tests

- Add 2 ETH-based validation tests to benchmark script
- Validates ExecuteBacktest_With_ETH_FifteenMinutes_Data_Should_Return_LightBacktest
- Validates ExecuteBacktest_With_ETH_FifteenMinutes_Data_Second_File_Should_Return_LightBacktest
- Ensures performance optimizations don't break trading logic
- Update command documentation with comprehensive validation details
- All 3 validation levels must pass for benchmark success

src/Managing.Application/Bots/TradingBotBase.cs

@@ -428,16 +428,7 @@ public class TradingBotBase : ITradingBot
             }
 
             // Check if we already have a position for this signal (in case it was added but not processed yet)
-            // Optimized: Avoid LINQ FirstOrDefault overhead
-            Position existingPosition = null;
-            foreach (var pos in Positions.Values)
-            {
-                if (pos.SignalIdentifier == signal.Identifier)
-                {
-                    existingPosition = pos;
-                    break;
-                }
-            }
+            var existingPosition = Positions.Values.FirstOrDefault(p => p.SignalIdentifier == signal.Identifier);
 
             if (existingPosition != null)
             {