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/tests/lcameraBuffParams_tests.cpp

@@ -0,0 +1,131 @@
+#include <lcameraBuffParams.h>
+#include <gtest/gtest.h>
+#include <support/exceptionAssertions.h>
+#include <user/deviceAttachmentSpec.h>
+
+namespace smo {
+namespace stim_buff {
+namespace lcamera_buff {
+namespace {
+
+device::DeviceAttachmentSpec makeSpecWithParams(
+	std::vector<std::pair<std::string, std::string>> params)
+{
+	device::DeviceAttachmentSpec spec;
+	spec.stimBuffApi = "lcameraBuff";
+	spec.provider = "lcameraDev";
+	spec.stimBuffApiParams = std::move(params);
+	return spec;
+}
+
+TEST(LcameraBuffParamsTest, DimWidthHeightSynonymsParseExplicitResolution)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"dim-w", "640"},
+		{"dimension-h", "480"},
+		{"colour-space", "yuv"},
+	});
+
+	const LcameraBuffParsedParams parsed = parseLcameraBuffParams(spec);
+
+	EXPECT_EQ(parsed.width, 640u);
+	EXPECT_EQ(parsed.height, 480u);
+	EXPECT_EQ(
+		parsed.colourSpace,
+		lcamera_dev::LcameraDevColourSpace::Yuv);
+	EXPECT_FALSE(parsed.fullPlanarIsOptional);
+}
+
+TEST(LcameraBuffParamsTest, VerticalResolutionShorthand480p)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"v-res", "480p"},
+		{"colour-space", "yuv"},
+		{"opt-planar", ""},
+	});
+
+	const LcameraBuffParsedParams parsed = parseLcameraBuffParams(spec);
+
+	EXPECT_EQ(parsed.width, 640u);
+	EXPECT_EQ(parsed.height, 480u);
+	EXPECT_TRUE(parsed.fullPlanarIsOptional);
+}
+
+TEST(LcameraBuffParamsTest, OptPlanarSynonymEmptyValueMeansTrue)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"v-res", "480p"},
+		{"full-planar-is-optional", ""},
+	});
+
+	EXPECT_TRUE(parseLcameraBuffParams(spec).fullPlanarIsOptional);
+}
+
+TEST(LcameraBuffParamsTest, OptPlanarExplicitFalseDisables)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"dim-w", "640"},
+		{"dim-h", "480"},
+		{"opt-planar", "false"},
+	});
+
+	EXPECT_FALSE(parseLcameraBuffParams(spec).fullPlanarIsOptional);
+}
+
+TEST(LcameraBuffParamsTest, OptPlanarAbsentDefaultsFalse)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"v-res", "480p"},
+	});
+
+	EXPECT_FALSE(parseLcameraBuffParams(spec).fullPlanarIsOptional);
+}
+
+TEST(LcameraBuffParamsTest, MixedResolutionGroupsThrow)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"v-res", "480p"},
+		{"dim-w", "640"},
+	});
+
+	try {
+		parseLcameraBuffParams(spec);
+		FAIL() << "Expected runtime_error";
+	}
+	catch (const std::runtime_error& exception)
+	{
+		sscl::tests::expectExceptionMessageContains(
+			exception,
+			"cannot be combined");
+	}
+}
+
+TEST(LcameraBuffParamsTest, UnsupportedColourSpaceThrows)
+{
+	device::DeviceAttachmentSpec spec = makeSpecWithParams({
+		{"v-res", "480"},
+		{"colour-space", "rgb"},
+	});
+
+	EXPECT_THROW(parseLcameraBuffParams(spec), std::runtime_error);
+}
+
+TEST(LcameraBuffParamsTest, ToCameraModeRequestCopiesFields)
+{
+	LcameraBuffParsedParams parsed;
+	parsed.width = 1280;
+	parsed.height = 720;
+	parsed.fullPlanarIsOptional = true;
+
+	const lcamera_dev::LcameraDevCameraModeRequest request =
+		toCameraModeRequest(parsed);
+
+	EXPECT_EQ(request.width, 1280u);
+	EXPECT_EQ(request.height, 720u);
+	EXPECT_TRUE(request.fullPlanarIsOptional);
+}
+
+} // namespace
+} // namespace lcamera_buff
+} // namespace stim_buff
+} // namespace smo