fix(android): resolve ArrayBuffer via app class loader on worker threads (JNI)

[lopadova]

Summary

• Fixes a runtime java.lang.ClassNotFoundException: ...com.margelo.nitro.core.ArrayBuffer ... DexPathList[... /system/lib64 ...] thrown when calling any command on an Android device.
• Root cause: the generated transport bridge resolves ArrayBuffer lazily in send() (JArrayBuffer::wrap → FindClass) on a Nitro worker thread. A plain fbjni ThreadScope only attaches a JNIEnv; it does NOT install the app class loader, so FindClass hits the system loader and fails. PR fix(android): create transport HybridObject on JS thread (fix ClassNotFound) #8 only cached our transport's jclass on the JS thread — it doesn't cover NitroModules core classes resolved later on worker threads.
• Fix: run all worker-thread C++→Kotlin JNI work under facebook::jni::ThreadScope::WithClassLoader, which attaches the thread AND installs fbjni's cached app class loader for the duration. New ECR17_RUN_ON_JVM_THREAD(body) macro wraps ensureConnected/runTransaction/runAckOnly (#ifdef __ANDROID__ → WithClassLoader; no-op inline on iOS), capturing the return value + exceptions (std::exception_ptr) so the money-safety try/catch logic (RetryPolicy / no blind financial retry) is unchanged.
• Keeps the complementary PR fix(android): create transport HybridObject on JS thread (fix ClassNotFound) #8 fix (createHybridObject on the JS thread in configure()).

Touches only package/cpp/Ecr17Client/HybridEcr17Client.cpp and docs/LESSON.md.

Test plan

• cpp-tests green (core unchanged)
• ts-checks green (no TS touched)
• android-build (manual dispatch) green — the ONLY verifier of the Nitro-integrated native code; cpp-tests does not compile the client
• Device smoke: calling a command no longer throws ClassNotFoundException for ArrayBuffer

🤖 Generated with Claude Code

[chatgpt-codex-connector]

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[Copilot]

Pull request overview

Fixes an Android runtime ClassNotFoundException when Nitro worker threads perform JNI FindClass (e.g., lazy com.margelo.nitro.core.ArrayBuffer resolution) by ensuring worker-thread JNI work runs with the app class loader installed.

Changes:

• Introduce ECR17_RUN_ON_JVM_THREAD(body) (Android: facebook::jni::ThreadScope::WithClassLoader, iOS: inline no-op) to run JNI work with the correct class loader.
• Wrap ensureConnected(), runTransaction(), and runAckOnly() JNI-dependent code paths in the new macro while preserving existing retry / “money-safety” exception semantics.
• Document the ArrayBuffer worker-thread class-loader failure mode and the WithClassLoader fix in docs/LESSON.md.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
package/cpp/Ecr17Client/HybridEcr17Client.cpp	Adds a WithClassLoader-based macro and applies it to worker-thread JNI call sites to fix class resolution on Android.
docs/LESSON.md	Adds a troubleshooting note describing the ArrayBuffer ClassNotFoundException root cause and the fix approach.

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[lopadova]

Thanks for the reviews — both addressed in b532a0c:

• Codex P1 (iOS bare return; in a non-void function): correct and important. The inline macro made the lambda's early return; compile inside the value-returning runTransaction on the iOS path (podspec globs cpp/**). Replaced the macro with a template helper runOnJvmThread(Fn) that always takes a callable — Android runs it under ThreadScope::WithClassLoader (capturing result/exception since WithClassLoader takes std::function<void()>), iOS calls it directly. return now exits only the lambda on both platforms; value-returning callers return runOnJvmThread(...). Verified both paths compile clean with g++ -std=c++20 -Wall -Wextra (with and without -D__ANDROID__).
• Copilot (reserved __ecr17Err): renamed to err.

Money-safety try/catch semantics unchanged.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.