}

    // Happy path: get -> release -> get returns same instance, zeroed on release
    @Test
    @DisplayName("Release stores buffer for reuse and zeroes its contents")
    void releaseStoresAndZeroesBuffer() {
        BufferCacheImpl impl = new BufferCacheImpl(2, 10);

        byte[] b = new byte[10];
        // Fill with non-zero to verify zeroing on release
        for (int i = 0; i < b.length; i++) {