Adds GetUnsettledCash to Settlement Model

See QuantConnect/Lean#7727

03 Writing Algorithms/24 Reality Modeling/07 Settlement/01 Key Concepts/04 Model Structure.html

@@ -34,6 +34,11 @@
     public void Scan(ScanSettlementModelParameters settlementParameters)
     {
     }
+
+    public CashAmount GetUnsettledCash()
+    {
+        return default;
+    }
 }</pre>
 <pre class='python'># In the Initialize method, set the custom settlement model
 security.SetSettlementModel(MySettlementModel())
@@ -46,10 +51,13 @@
         applyFundsParameters.Portfolio.CashBook[currency].AddAmount(amount)
 
     def Scan(self, settlementParameters: ScanSettlementModelParameters) -> None:
-        pass</pre>
+        pass
+
+    def GetUnsettledCash(self) -> CashAmount:
+        return None</pre>
 </div>
 
-<p>For a full example algorithm, see <span class='python'><a href='https://www.quantconnect.com/terminal/processCache?request=embedded_backtest_a27d38bfde7135a8345c8783910be29e.html'>this backtest</a></span><span class='csharp'><a href='https://www.quantconnect.com/terminal/processCache?request=embedded_backtest_d00175b971c1a3f8d498f619944fdcaa.html'>this backtest</a></span>.</p>
+<p>For a full example algorithm, see <span class='python'><a href='https://www.quantconnect.com/terminal/processCache?request=embedded_backtest_8b7e4a221b5f846a141468e382a1a526.html'>this backtest</a></span><span class='csharp'><a href='https://www.quantconnect.com/terminal/processCache?request=embedded_backtest_510b44847f10e72d158a5de0072609ef.html'>this backtest</a></span>.</p>
 
 <p><code>ApplyFundsSettlementModelParameters</code> objects have the following properties:</p>
 <div data-tree="QuantConnect.Securities.ApplyFundsSettlementModelParameters"></div>