fix: add ProgramData path validation for Windows config directory test

The GetConfigDir test was failing on Windows when APPDATA environment
variable is not set, as the fallback path uses C:\ProgramData\hosts-manager.
Updated test validation to accept ProgramData as a valid path component
alongside AppData, .config, and /etc/.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: Brandon Honeycutt

pkg/platform/platform_test.go

@@ -64,6 +64,7 @@ func TestGetConfigDir(t *testing.T) {
 				return strings.Contains(path, "hosts-manager") &&
 					(strings.Contains(path, ".config") ||
 						strings.Contains(path, "AppData") ||
+						strings.Contains(path, "ProgramData") ||
 						strings.Contains(path, "/etc/"))
 			},
 		},