fix(loader): anchor native-library resource path to fixed package root

LlamaLoader.getNativeResourcePath() derived the classpath location of the
bundled native libraries from the loader's OWN Java package via
LlamaLoader.class.getPackage(). The layered restructure moved LlamaLoader from
net.ladenthin.llama to net.ladenthin.llama.loader, so the lookup became
/net/ladenthin/llama/loader/<os>/<arch>/libjllama.so — one directory too deep.
CMakeLists.txt and the publish workflow emit the libs to the fixed layout
/net/ladenthin/llama/<os>/<arch>/, so getResource(...) returned null and every
native-backed test failed at runtime with "No native library found" (and the
packaged JAR would fail identically for real consumers).

Fix: anchor the resource root to a NATIVE_RESOURCE_BASE constant
("/net/ladenthin/llama") independent of the loader's Java package, matching the
build/CI layout. Adds a regression test pinning the exact prefix and asserting
the path never contains "/loader/" (the pre-existing contains-substring test
stayed green through the bug, which is why it slipped in).

Same class of latent "path derived from something that moved in the restructure"
bug as the spotbugs-exclude / PIT-target / CMake-OSInfo FQN repairs.

Author: claude

src/main/java/net/ladenthin/llama/loader/LlamaLoader.java

@@ -48,6 +48,15 @@ public class LlamaLoader {
     private static final LlamaSystemProperties systemProperties = new LlamaSystemProperties();
     private static final NativeLibraryPermissionSetter permissionSetter = new NativeLibraryPermissionSetter(System.err);
 
+    /**
+     * Canonical classpath root for the bundled native libraries. Fixed by
+     * {@code CMakeLists.txt} and the publish workflow (both emit to
+     * {@code resources/net/ladenthin/llama/<os>/<arch>/}); it must NOT be
+     * derived from this loader's own Java package, which moved to
+     * {@code net.ladenthin.llama.loader} during the layered restructure.
+     */
+    private static final String NATIVE_RESOURCE_BASE = "/net/ladenthin/llama";
+
     /** Static utility holder; not instantiable. */
     private LlamaLoader() {}
 
@@ -267,14 +276,7 @@ static File getTempDir() {
     }
 
     static String getNativeResourcePath() {
-        final Package pkg = LlamaLoader.class.getPackage();
-        // LlamaLoader is in a named package, so Class.getPackage() is never null here.
-        if (pkg == null) {
-            throw new IllegalStateException("LlamaLoader.class.getPackage() returned null (classLoader="
-                    + LlamaLoader.class.getClassLoader() + ")");
-        }
-        String packagePath = pkg.getName().replace('.', '/');
-        return String.format("/%s/%s", packagePath, OSInfo.getNativeLibFolderPathForCurrentOS());
+        return String.format("%s/%s", NATIVE_RESOURCE_BASE, OSInfo.getNativeLibFolderPathForCurrentOS());
     }
 
     private static boolean hasNativeLib(String path, String libraryName) {

src/test/java/net/ladenthin/llama/loader/LlamaLoaderTest.java

@@ -187,4 +187,24 @@ public void testGetNativeResourcePathContainsOsAndArch() {
         String osArch = OSInfo.getNativeLibFolderPathForCurrentOS();
         assertTrue(path.endsWith(osArch), "Resource path should end with OS/arch: " + path);
     }
+
+    /**
+     * Regression for the layered-restructure bug: the native-library classpath
+     * root is fixed at {@code /net/ladenthin/llama/<os>/<arch>} by CMakeLists +
+     * the publish workflow, so it must NOT track the loader's own Java package
+     * (which moved to {@code net.ladenthin.llama.loader}). Deriving it from
+     * {@code LlamaLoader.class.getPackage()} produced {@code .../llama/loader/...},
+     * one level too deep, so {@code getResource(...)} returned null and every
+     * native-backed test failed with "No native library found".
+     */
+    @Test
+    public void testGetNativeResourcePathIsPackageIndependent() {
+        String path = LlamaLoader.getNativeResourcePath();
+        String osArch = OSInfo.getNativeLibFolderPathForCurrentOS();
+        assertEquals("/net/ladenthin/llama/" + osArch, path);
+        assertFalse(
+                path.contains("/loader/"),
+                "Resource path must not include the loader subpackage — the native libs live at "
+                        + "/net/ladenthin/llama/<os>/<arch>, not under the loader package: " + path);
+    }
 }