Add project files.

FreedomFighter/Program.cs

@@ -0,0 +1,17 @@
+using System;
+
+using var game = new FreedomFighter.Game1();
+// debug aid: --shot <file> [frames] renders, saves the backbuffer to a PNG, and exits
+var cmdArgs = Environment.GetCommandLineArgs();
+for (int i = 1; i < cmdArgs.Length - 1; i++)
+{
+    if (cmdArgs[i] == "--shot")
+    {
+        game.ShotFile = cmdArgs[i + 1];
+        if (i + 2 < cmdArgs.Length && int.TryParse(cmdArgs[i + 2], out int frames))
+            game.ShotFrames = frames;
+    }
+    if (cmdArgs[i] == "--level" && int.TryParse(cmdArgs[i + 1], out int level))
+        game.StartLevel = level;
+}
+game.Run();