Fix WinlatorEngine compilation errors

- Add ObservableObject conformance to WinlatorEngine
- Fix Process import issue (Foundation already includes Process)
- Resolve StateObject generic constraint error
- Enable proper SwiftUI integration with engine state

Author: devz906

App/WinlatorEngine.swift

@@ -1,7 +1,7 @@
 import Foundation
 import UIKit
 
-class WinlatorEngine {
+class WinlatorEngine: ObservableObject {
     static let shared = WinlatorEngine()
 
     private var process: Process?