fixed (bug) Audio not looping after ending.

tests/test_audio.cpp

@@ -59,3 +59,14 @@ TEST(AudioTest, AudioManagerVolumeClamping) {
     am.shutdown();
     std::filesystem::remove(temp_path);
 }
+
+TEST(AudioTest, PlayOptionsLoopInfinite) {
+    // Regression: MIX_PlayTrack() must not default to a single pass. Tracks
+    // have to loop forever so playback never runs out mid-scroll; a track that
+    // stops (rather than attenuates) also can't be revived by raising app
+    // volume. Assert the options request infinite looping (-1).
+    SDL_PropertiesID props = AudioManager::createInfiniteLoopOptions();
+    ASSERT_NE(props, 0u);
+    EXPECT_EQ(SDL_GetNumberProperty(props, MIX_PROP_PLAY_LOOPS_NUMBER, 0), -1);
+    SDL_DestroyProperties(props);
+}