add csharp snippets

snippets/csharp/GettingStarted.cs

@@ -0,0 +1,62 @@
+using Breez.Sdk;
+
+public class GettingStartedSnippets
+{
+    // ANCHOR: init-sdk
+    public void GettingStarted()
+    {
+        // Create the default config
+        var seed = BreezSdkMethods.MnemonicToSeed("<mnemonic words>");
+        var inviteCode = "<invite code>";
+        var apiKey = "<api key>";
+        var nodeConfig = new NodeConfig.Greenlight(
+            new GreenlightNodeConfig(null, inviteCode)
+        );
+        var config = BreezSdkMethods.DefaultConfig(
+            EnvironmentType.PRODUCTION,
+            apiKey,
+            nodeConfig
+        ) with
+        {
+            // Customize the config object according to your needs
+            workingDir = "path to an existing directory"
+        };
+
+        BlockingBreezServices sdk;
+        try
+        {
+            // Connect to the Breez SDK make it ready for use
+            sdk = BreezSdkMethods.Connect(config, seed, new SdkListener());
+        }
+        catch (Exception)
+        {
+            // Handle error
+        }
+    }
+
+    // SDK event listener
+    class SdkListener : EventListener
+    {
+        public void OnEvent(BreezEvent e)
+        {
+            Console.WriteLine($"Received Breez event type {e.GetType().Name}");
+        }
+    }
+    // ANCHOR_END: init-sdk
+
+    public void FetchNodeInfo(BlockingBreezServices sdk)
+    {
+        // ANCHOR: fetch-balance
+        try
+        {
+            var nodeInfo = sdk.NodeInfo();
+            var lnBalance = nodeInfo?.channelsBalanceMsat;
+            var onchainBalance = nodeInfo?.onchainBalanceMsat;
+        }
+        catch (Exception)
+        {
+            // Handle error
+        }
+        // ANCHOR_END: fetch-balance
+    }
+}