e6988edd0d
Crash: DisposableEffect.onDispose called nativeClose(handle) (Box::from_raw frees the SessionHandle) while the SurfaceView's surfaceDestroyed independently called nativeStopVideo/Audio/Mic on the same handle -- whichever ran after the close dereferenced freed memory (SIGSEGV: the consistent back-navigation crash). Add a one-shot `closed` guard: onDispose marks it before freeing; surfaceDestroyed skips the native calls once closed (backgrounding still stops the threads when it wins). Polish: - Branded Material You theme (Theme.kt): dynamic colour on Android 12+, punktfunk brand violets as the pre-12 fallback, replacing the generic darkColorScheme(). - ConnectScreen: "Connecting..." was rendered in error-red with no spinner; now a neutral spinner while connecting, red reserved for actual errors. Verified locally: ./gradlew :app:assembleDebug BUILD SUCCESSFUL (both ABIs + the Compose changes), debug APK assembles. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>