Refactor order count checks for asks and bids

Store asks and bids counts in variables to avoid repeated enumeration and improve readability. Updated null and count checks to use these variables throughout the order imbalance calculation logic.

Author: Ariel Silahian

VisualHFT.Commons/Studies/OrderFlowAnalysis.cs

@@ -107,16 +107,18 @@ It can provide insights into the supply and demand dynamics in the market.
             A positive order imbalance (more buy orders than sell orders) can indicate upward pressure on prices, while a negative order imbalance (more sell orders than buy orders) can indicate downward pressure on prices.
             */
 
-            if (asks != null && bids != null && asks.Count() > 0 && bids.Count() > 0)
+            int asksCount = asks?.Count() ?? 0;
+            int bidsCount = bids?.Count() ?? 0;
+            if (asksCount > 0 && bidsCount > 0)
             {
                 double totalAskSize = 0;
                 double totalBidSize = 0;
 
                 for (int i = 0; i < _bookDepth; i++)
                 {
-                    if (i < asks.Count())
+                    if (i < asksCount)
                         totalAskSize += asks[i].Size.Value;
-                    if (i < bids.Count())
+                    if (i < bidsCount)
                         totalBidSize += bids[i].Size.Value;
                 }