llama : correct platform-independent loading of BOOL metadata (#21428)

* model-loader : fix GGUF bool array conversion

* model-loader : fix remaining GGUF bool pointer uses

src/llama-model-loader.cpp

@@ -374,8 +374,9 @@ namespace GGUFMeta {
             }
         } else {
             if (arr_info.gt == GGUF_TYPE_BOOL) {
-                std::transform((const bool *)arr_info.data, (const bool *)arr_info.data + arr_info.length, result.begin(), [](bool x) {
-                    return static_cast<T>(x);
+                const int8_t * values = (const int8_t *) arr_info.data;
+                std::transform(values, values + arr_info.length, result.begin(), [](int8_t x) {
+                    return static_cast<T>(x != 0);
                 });
             } else {
                 std::copy((const T*)arr_info.data, (const T *)arr_info.data + arr_info.length, result.begin());