Add lcameraBuff Stage 2 plugin with YUV attach and unit tests.

Introduce params parsing, pixel/format decisions, capture layout, shared
YuvStimProducer per camera, and channel stimulus buffers with attach flow.

Co-authored-by: Cursor <cursoragent@cursor.com>

stimBuffApis/lcameraBuff/yuvCaptureLayout.h

@@ -0,0 +1,33 @@
+#ifndef LCAMERA_BUFF_YUV_CAPTURE_LAYOUT_H
+#define LCAMERA_BUFF_YUV_CAPTURE_LAYOUT_H
+
+#include <cameraModeRequest.h>
+
+namespace smo {
+namespace stim_buff {
+namespace lcamera_buff {
+
+enum class YuvCaptureLayoutPath
+{
+	FullPlanarDirect,
+	SemiPlanarDeinterleave,
+	PackedDeinterleave,
+};
+
+enum class YuvChannelBackingPlan
+{
+	LCameraDirect,
+	MmapDeinterleaved,
+};
+
+YuvCaptureLayoutPath classifyYuvCaptureLayoutPath(
+	const lcamera_dev::LcameraDevConfiguredCameraMode& configuredMode);
+
+YuvChannelBackingPlan getChannelBackingPlanForLayoutPath(
+	YuvCaptureLayoutPath layoutPath);
+
+} // namespace lcamera_buff
+} // namespace stim_buff
+} // namespace smo
+
+#endif // LCAMERA_BUFF_YUV_CAPTURE_LAYOUT_H