Flutter3.38.5. Entry: lib/main_lokomotiv_preview.dart. Windows: set LOKOMOTIV_PREVIEW=1, then flutter build windows --release --target lib/main_lokomotiv_preview.dart --build-name=0.1.0 --build-number=1. Android: scripts/build-lokomotiv-android.sh; requires own signing config and native support AAR. Android preview retains inherited native support, VPN startup is blocked. Windows preview excludes VPN runtime entirely. No working VPN/auth/payment in preview. Source revision: 0d50abe6779cffd6c272e9e1f3e6d4565cabec0e
