My Flutter app builds fine, yet the moment the simulator launches the interface never appears— all I get is a solid black screen right from startup. Logs stay mostly quiet and the app doesn’t crash or freeze; it just never renders the first frame. I need someone to trace the root cause of this startup black-out, correct it in the codebase, then verify that the fix works on both iOS Simulator and Android Emulator. Acceptance criteria: • Clear explanation of what caused the black screen. • Code changes (pull request or patch) that resolve the issue. • Confirmation, with screenshots or short recording, showing the first screen loading correctly on at least one iOS and one Android virtual device. The project uses the standard Flutter toolchain; feel free to employ Flutter DevTools, Xcode, Android Studio, or any debugging method you prefer as long as the final result is a clean, reproducible fix.