Move projects to src; add Neutrino secret

src/RecNet.Infrastructure/Services/Steam/SteamOptions.cs

@@ -0,0 +1,8 @@
+namespace RecNet.Infrastructure.Services.Steam;
+
+public class SteamOptions
+{
+    public string ApiKey { get; set; } = string.Empty;
+    public uint AppId { get; set; } = 480; // Spacewar
+    public string Identity { get; set; } = "recnet";
+}