feat: Windows Setup Wizard (ostp-setup) with Tauri

- Tauri 2.0 based graphical installer
- Access Key parsing with AES-256-GCM encryption
- Windows Service installation via sc.exe
- WinTUN driver extraction from embedded resources
- System requirements checking (admin, AES-NI, OS version)
- Modern dark UI with step-by-step wizard flow
- Country/region selection for SNI mimicry

ostp-setup/build.rs

@@ -0,0 +1,3 @@
+fn main() {
+    tauri_build::build()
+}