livoxGen1: Implement StimBuff add/del from StimProducers

There seems to be a bug where two or more stimProducers
or stimBuffs get initialized at once but we can deal with that
tomorrow.

stimBuffApis/livoxGen1/pcloudStimulusProducer.cpp

@@ -100,6 +100,28 @@ void produceStimFrameAck(void)
 {
 }
 
+std::shared_ptr<StimulusBuffer>
+PcloudStimulusProducer::getOrCreateAttachedStimulusBuffer(
+	const std::shared_ptr<device::DeviceAttachmentSpec>& deviceAttachmentSpec,
+	int histbuffMs
+	)
+{
+	// Check if buffer already exists (idempotent)
+	auto existingBuffer = getAttachedStimulusBuffer(deviceAttachmentSpec);
+	if (existingBuffer)
+		{ return existingBuffer; }
+
+	// Create new PcloudXyzStimulusBuffer (for now, always use XYZ type)
+	auto buffer = std::make_shared<PcloudXyzStimulusBuffer>(
+		*this, deviceAttachmentSpec, histbuffMs, openClInputConstraints);
+
+	// Add to collection
+	attachedStimulusBuffers.push_back(buffer);
+	// Update specialized member
+	xyzStimulusBuffer = buffer;
+	return buffer;
+}
+
 void PcloudStimulusProducer::stimFrameProductionTimesliceInd()
 {
 	produceFrameReq({nullptr, nullptr});