Standalone test app to validate Quest OpenXR + Passthrough AR support before integrating into fastn-shell.

1. OpenXR instance creation on Quest
2. Extension enumeration (especially XR_FB_passthrough)
3. System/HMD detection
4. View configuration

# macOS with Homebrew
brew install openjdk@17
brew install android-ndk
brew install android-commandlinetools

# Or download from https://developer.android.com/ndk/downloads

cargo install cargo-apk

rustup target add aarch64-linux-android

1. Download from: https://developer.oculus.com/downloads/package/oculus-openxr-mobile-sdk/
2. Extract libopenxr_loader.so from OpenXR/Libs/Android/arm64-v8a/Release/
3. Place in quest-test/libs/arm64-v8a/libopenxr_loader.so

mkdir -p libs/arm64-v8a
# Copy libopenxr_loader.so there

1. Create developer account at https://developer.oculus.com/
2. Enable Developer Mode in Oculus mobile app
3. Connect Quest via USB and allow debugging

# Build APK
cargo apk build --release

# Install to connected Quest
adb install -r target/release/apk/quest-test.apk

# Watch logs
adb logcat -s quest-test:* RustStdoutStderr:*

You should see output like:

=== Quest OpenXR Test Started ===
Initializing OpenXR...
Available OpenXR extensions:
  KHR_vulkan_enable2: true
  FB_passthrough: true
OpenXR runtime: Oculus v1.x.x
System: Oculus Quest 3
Passthrough support: true
SUCCESS: This device supports AR passthrough!

You can verify the code compiles on desktop:

cargo check
cargo run  # Will fail at runtime without VR runtime, but checks compilation

Once this test confirms passthrough support:

1. Add Vulkan rendering (render a cube in VR)
2. Enable passthrough layer (AR mode)
3. Integrate into fastn-shell as Android target

export JAVA_HOME="/opt/homebrew/opt/openjdk@17" export PATH="/opt/homebrew/opt/openjdk@17/bin:$PATH" export ANDROID_HOME="/opt/homebrew/share/android-commandlinetools" export ANDROID_NDK_HOME="/opt/homebrew/share/android-ndk"