Fix release publish: reconstruct native artifact paths

[devcrocod]

Problem

The 0.1.0 release publish failed at Copy Android natives to jniLibs:

cp: simdjson-native/build-android-arm64-v8a/libsimdjson_jni.so: No such file or directory

Root cause: the publish job assumed downloaded native artifacts kept their full simdjson-native/build-*/… repo-relative paths. But actions/upload-artifact roots each artifact at the least-common-ancestor of its path entries:

• multi-file artifacts (native-android, native-kn-ios) lose the simdjson-native/ prefix → keep only build-*/lib;
• single-file artifacts (all desktop JNI/KN) collapse to a bare filename.

With download-artifact --merge-multiple into the repo root, the Android .sos landed at build-android-*/… (so the cp failed — the observed error), and the JNI/KN libraries collided at the repo root (two libsimdjson_jni.so, two libsimdjson_c.a), invisible to Gradle. Even after fixing Android, Publish would then fail the -Psimdjson.allTargets=true requireAllNatives check for linux-x64/linux-arm64/windows, and the linuxX64 cinterop would miss its static .a.

Fix

Download each artifact into its own directory (path: artifacts, no merge-multiple) and reconstruct the exact tree the publish expects via an explicit stage() helper. Only cross-compiled libraries are staged (linux-x64/linux-arm64/windows JNI, linux-x64 KN .a, both Android ABIs → jniLibs/); host-native libraries (macos-arm64 JNI, macOS/iOS .a) are rebuilt on the runner.

Verification

Simulated the new stage() steps against the real 8 artifacts from the failed run — all 6 required destination paths are reconstructed correctly; YAML validated. The full publishToMavenCentral itself can't be run locally (needs Sonatype/signing secrets), so credential/POM-level issues, if any, would only surface on a real run.

[Copilot]

Pull request overview

This PR fixes the Maven Central release workflow by avoiding artifact path collisions/flattening from actions/upload-artifact, and explicitly staging downloaded native libraries back into the repository layout that the Gradle publish expects.

Changes:

• Download all native artifacts into a dedicated artifacts/ directory (no merge into repo root).
• Add a stage() helper to reconstruct expected repo-relative native library paths before publishing.
• Stage only cross-compiled natives (Linux/Windows JNI, Linux KN .a, Android .sos), relying on the macOS runner to rebuild host-native outputs.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.