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/lcameraBuffParams.h

@@ -0,0 +1,34 @@
+#ifndef LCAMERA_BUFF_PARAMS_H
+#define LCAMERA_BUFF_PARAMS_H
+
+#include <cameraModeRequest.h>
+#include <user/deviceAttachmentSpec.h>
+
+namespace smo {
+namespace stim_buff {
+namespace lcamera_buff {
+
+struct LcameraBuffParsedParams
+{
+	unsigned width = 0;
+	unsigned height = 0;
+	lcamera_dev::LcameraDevColourSpace colourSpace =
+		lcamera_dev::LcameraDevColourSpace::Yuv;
+	bool fullPlanarIsOptional = false;
+};
+
+LcameraBuffParsedParams parseLcameraBuffParams(
+	const device::DeviceAttachmentSpec& spec);
+
+lcamera_dev::LcameraDevCameraModeRequest toCameraModeRequest(
+	const LcameraBuffParsedParams& parsedParams);
+
+bool lcameraBuffParamsEqual(
+	const LcameraBuffParsedParams& left,
+	const LcameraBuffParsedParams& right);
+
+} // namespace lcamera_buff
+} // namespace stim_buff
+} // namespace smo
+
+#endif // LCAMERA_BUFF_PARAMS_H