Update native library dev documentation

Author: lesserwhirls

native-compression/README

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+# Updating Native Jars
+
+Updating a native jar requires at least two commits.
+The first commit updates a GitHub workflow that generates the native libraries using GitHub Actions; the second will update the `*-native` subproject build to use the new native libraries.
+1. The `native-compression/*-native` subprojects depend on a .zip file and checksum file that contain the native libraries, which are hosted on Unidata servers.
+These files are generated on GitHub using the `.github/worlflows/lib*.yml`.
+To update a native jar, you first update the associated workflow.
+Once the workflow is on the main branch (currently `maint-5.x`), manually trigger the workflow on GitHub.
+The workflow output will provide a zip file and sha-256 checksum value.
+2. Copy the zip file generated by the workflow in step 1 to the Unidata server and generate a checksum for the file.
+Update the `native-compression/lib*-native/build.gradle.kts` file with the new version information and checksum value from the GitHub output.
+If everything looks good, and the draft PR with these changes passes, update the documentation to reflect the latest version of the native jar (see `docs/src/site/_config.yml`).
+Once these changes are merged, the final step is to publish a new native jar.
+
+## Publishing Native Jars
+
+The native jars are versioned based on the native library version (plus a build number).
+These jars are also published separate to the rest of the project jars.
+To publish a native jar, you must set the `unidata.native.publish=true` system property when running the Gradle publish command.
+For example, to publish the libblosc2-native jar, run:
+
+```
+./gradlew -D"unidata.native.publish=true" :libblosc2-native:publish
+```