fix(jni): update FindClass FQNs for classes moved in the layered restructure

JNI_OnLoad resolves a handful of Java classes by hardcoded path via
env->FindClass(...). The layered restructure moved two of them into
subpackages, but the C++ paths still pointed at the old flat package, so once
the native library actually loaded (after the LlamaLoader resource-path fix),
JNI_OnLoad failed at load time with
  NoClassDefFoundError: net/ladenthin/llama/LogLevel
and every native-backed Java test errored in LlamaModel.<clinit>.

Corrected the stale paths to match the current packages:
- net/ladenthin/llama/LlamaException -> net/ladenthin/llama/exception/LlamaException
- net/ladenthin/llama/LogLevel       -> net/ladenthin/llama/value/LogLevel
  (FindClass + the four GetStaticFieldID "L...;" field signatures)

LlamaModel (root) and args/LogFormat were already correct; LoadProgressCallback
appears only in a comment in the generated jllama.h (regenerated by javac -h),
not in a FindClass, so it needs no change.

Verified locally: incremental native rebuild + forcing LlamaModel.<clinit>
(System.load -> JNI_OnLoad) now completes with no NoClassDefFoundError — the
JNI class lookups resolve. Same stale-FQN-after-restructure class as the
LlamaLoader resource-path, spotbugs-exclude, PIT-target and CMake-OSInfo repairs.

Author: claude

src/main/cpp/jllama.cpp

@@ -479,8 +479,8 @@ JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *vm, void *reserved) {
     c_integer = env->FindClass("java/lang/Integer");
     c_float = env->FindClass("java/lang/Float");
     c_biconsumer = env->FindClass("java/util/function/BiConsumer");
-    c_llama_error = env->FindClass("net/ladenthin/llama/LlamaException");
-    c_log_level = env->FindClass("net/ladenthin/llama/LogLevel");
+    c_llama_error = env->FindClass("net/ladenthin/llama/exception/LlamaException");
+    c_log_level = env->FindClass("net/ladenthin/llama/value/LogLevel");
     c_log_format = env->FindClass("net/ladenthin/llama/args/LogFormat");
     c_error_oom = env->FindClass("java/lang/OutOfMemoryError");
 
@@ -527,10 +527,10 @@ JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *vm, void *reserved) {
     // find fields
     f_model_pointer = env->GetFieldID(c_llama_model, "ctx", "J");
     f_utf_8 = env->GetStaticFieldID(c_standard_charsets, "UTF_8", "Ljava/nio/charset/Charset;");
-    f_log_level_debug = env->GetStaticFieldID(c_log_level, "DEBUG", "Lnet/ladenthin/llama/LogLevel;");
-    f_log_level_info = env->GetStaticFieldID(c_log_level, "INFO", "Lnet/ladenthin/llama/LogLevel;");
-    f_log_level_warn = env->GetStaticFieldID(c_log_level, "WARN", "Lnet/ladenthin/llama/LogLevel;");
-    f_log_level_error = env->GetStaticFieldID(c_log_level, "ERROR", "Lnet/ladenthin/llama/LogLevel;");
+    f_log_level_debug = env->GetStaticFieldID(c_log_level, "DEBUG", "Lnet/ladenthin/llama/value/LogLevel;");
+    f_log_level_info = env->GetStaticFieldID(c_log_level, "INFO", "Lnet/ladenthin/llama/value/LogLevel;");
+    f_log_level_warn = env->GetStaticFieldID(c_log_level, "WARN", "Lnet/ladenthin/llama/value/LogLevel;");
+    f_log_level_error = env->GetStaticFieldID(c_log_level, "ERROR", "Lnet/ladenthin/llama/value/LogLevel;");
     f_log_format_json = env->GetStaticFieldID(c_log_format, "JSON", "Lnet/ladenthin/llama/args/LogFormat;");
     f_log_format_text = env->GetStaticFieldID(c_log_format, "TEXT", "Lnet/ladenthin/llama/args/LogFormat;");