Refactor audio handling with range checks, buffer threshold, and lock fixes

- Added range checks for handle to avoid invalid index access in AudioOutOutput, AudioOutSetVolume, and AudioOutGetStatus.

- Added a constant AUDIO_STREAM_BUFFER_THRESHOLD for the buffer threshold (was previously a magic number).

- Set the freq parameter correctly in the SDL_AudioSpec structure in AudioOutOpen.

- Fixed locking issues in AudioOutOutput to avoid unlocking before it's locked.

- Removed tab spaces to fix format clang error

src/audio_core/sdl_audio.cpp

@@ -98,22 +98,22 @@ s32 SDLAudio::AudioOutOutput(s32 handle, const void* ptr) {
         return ORBIS_AUDIO_OUT_ERROR_INVALID_PORT;
     }
 
+    if (ptr == nullptr) {
+        return 0; // Nothing to output
+    }
+
     std::shared_lock lock{m_mutex};
     auto& port = portsOut[handle - 1];
     if (!port.isOpen) {
         return ORBIS_AUDIO_OUT_ERROR_INVALID_PORT;
     }
-	if (ptr == nullptr) {
-		return 0;
-	}
 
-	// TODO mixing channels
-	SDL_bool result = SDL_PutAudioStreamData(
-		port.stream, ptr, port.samples_num * port.sample_size * port.channels_num);
+    const size_t data_size = port.samples_num * port.sample_size * port.channels_num;
 
-	lock.unlock(); // Unlock after the critical section
+    SDL_bool result = SDL_PutAudioStreamData(port.stream, ptr, data_size);
+
+    lock.unlock(); // Unlock only after necessary operations
 
-	// TODO find a correct value 8192 is estimated
     while (SDL_GetAudioStreamAvailable(port.stream) > AUDIO_STREAM_BUFFER_THRESHOLD) {
         SDL_Delay(0);
     }