add csharp snippets

snippets/csharp/LnurlWithdraw.cs

@@ -0,0 +1,31 @@
+using Breez.Sdk;
+
+public class LnurlWithdrawSnippets
+{
+    public void LnurlWithdraw(BlockingBreezServices sdk)
+    {
+        // ANCHOR: lnurl-withdraw
+        // Endpoint can also be of the form:
+        // lnurlw://domain.com/lnurl-withdraw?key=val
+        var lnurlWithdrawUrl = "lnurl1dp68gurn8ghj7mr0vdskc6r0wd6z7mrww4exctthd96xserjv9mn7um9wdekjmmw843xxwpexdnxzen9vgunsvfexq6rvdecx93rgdmyxcuxverrvcursenpxvukzv3c8qunsdecx33nzwpnvg6ryc3hv93nzvecxgcxgwp3h33lxk";
+
+        try
+        {
+            var input = BreezSdkMethods.ParseInput(lnurlWithdrawUrl);
+            if (input is InputType.LnUrlWithdraw lnurlw)
+            {
+                var amountMsat = lnurlw.data.minWithdrawable;
+                var result = sdk.WithdrawLnurl(
+                    new LnUrlWithdrawRequest(
+                        lnurlw.data,
+                        amountMsat,
+                        "comment"));
+            }
+        }
+        catch (Exception)
+        {
+            // Handle error
+        }
+        // ANCHOR_END: lnurl-withdraw
+    }
+}