fix: wait for Android exposure capture readiness

[mrousavy]

Summary

This keeps Android CameraSession.start() scoped to CameraX camera-state readiness, and moves capture-result readiness to the controller operation that actually needs it: supported, in-range, state-changing setExposureBias(...) calls.

It also keeps the Device Farm/Harness CI hardening from earlier commits:

• package Bun into Device Farm test packages instead of relying on network install inside Device Farm
• print Device Farm diagnostics when Harness artifacts are missing

Why

The Harness diagnostic run for visioncamera.controller.harness.ts showed the Android bridge timeout happened while the controller test was running:

Last started test before the device stopped responding: VisionCamera - Controller sets exposure bias to min/max when the device supports it

CameraX exposure compensation futures complete from capture results. Waiting only for CameraState.OPEN is not always strong enough: the camera can be open while the capture-result pipeline has not yet produced the metadata CameraX uses to complete setExposureCompensationIndex(...).

A previous attempt waited for the first capture result in every CameraSession.start(). That made the controller suite pass once, but it was too broad: valid multi-output starts can have no consumer attached yet and should not fail just because no capture result is produced at start. This revision removes that global start wait and only fences the exposure-bias path that the logs identified.

If the camera is open but no capture result arrives before applying exposure bias, the controller now fails after 5s with a specific native error instead of letting the Harness file-level RPC timeout burn roughly 120s. Invalid or no-op exposure-bias calls skip the readiness wait and still go through CameraX directly.

Verification

• bun run lint-kotlin -- packages/react-native-vision-camera/android/src/main/java/com/margelo/nitro/camera/hybrids/HybridCameraController.kt packages/react-native-vision-camera/android/src/main/java/com/margelo/nitro/camera/hybrids/HybridCameraSession.kt
• cd apps/simple-camera/android && JAVA_HOME=/opt/homebrew/opt/openjdk@17 ./gradlew :react-native-vision-camera:compileDebugKotlin --no-daemon --console=plain

Device Farm is running again on 34b52f0c to verify that the Android controller suite still runs and the multi-output regression from the global start wait is gone.

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Project	Deployment	Actions	Updated (UTC)
react-native-vision-camera-docs	Ready	Preview, Comment	Jun 5, 2026 10:13am

[mrousavy]

i think this is BS, CameraX should allow us operating with the Camera after start() completed I think