feat: initial project structure with Snake.Core, CLI and Avalonia skeleton

Snake.CLI/Program.cs

@@ -0,0 +1,44 @@
+using Snake.CLI;
+using Snake.Core;
+
+const int boardWidth = 20;
+const int boardHeight = 15;
+const int tickMs = 120;
+
+SnakeGame game = new(boardWidth, boardHeight);
+ConsoleRenderer.Render(game);
+
+while (true)
+{
+    if (Console.KeyAvailable)
+    {
+        var key = Console.ReadKey(intercept: true).Key;
+
+        switch (key)
+        {
+            case ConsoleKey.UpArrow:
+                game.SetDirection(Direction.Up);
+                break;
+            case ConsoleKey.DownArrow:
+                game.SetDirection(Direction.Down);
+                break;
+            case ConsoleKey.LeftArrow:
+                game.SetDirection(Direction.Left);
+                break;
+            case ConsoleKey.RightArrow:
+                game.SetDirection(Direction.Right);
+                break;
+            case ConsoleKey.Q:
+                return;
+            case ConsoleKey.R when game.IsGameOver:
+                game = new SnakeGame(boardWidth, boardHeight);
+                break;
+        }
+    }
+
+    if (!game.IsGameOver)
+        game.Tick();
+
+    ConsoleRenderer.Render(game);
+    Thread.Sleep(tickMs);
+}