Aggiunto supporto al motore CLI Antigravity (agy)

Core/EngineUpdater.cs

@@ -126,6 +126,8 @@ static class EngineUpdater
         ("codex", _) => OperatingSystem.IsWindows()
             ? "powershell -ExecutionPolicy ByPass -c \"irm https://chatgpt.com/codex/install.ps1 | iex\""
             : "curl -fsSL https://chatgpt.com/codex/install.sh | sh",
+        ("agy", InstallMethod.Homebrew) => "brew upgrade agy",
+        ("agy", _) => "agy update",
         _ => $"{engine.Executable} update",
     };
 }