color: input colorspace auto-detection, HDR export tags, LGG/white balance nodes, more LUT formats, waveform parade

- media color primaries/transfer tags now flow from the FFmpeg probe
  through VideoParams into Footage::get_colorspace_to_use(); precedence
  is user override > media tags > project default
- export nclc tags derive from the output colorspace (PQ/HLG/BT.2020,
  P3, sRGB, Rec.601, Rec.709) instead of hardcoded BT.709
- new OCIO Color Grading (Log) node (lift/gamma/gain) and White Balance
  node (kelvin temperature + tint, HDR-safe)
- LUT whitelist extended to 9 OCIO-supported formats
- waveform scope gains an RGB parade mode (GPU and software paths)
- tests updated for the new colorspace precedence

tests/gtest/codec_decoder_test.cpp

@@ -41,3 +41,22 @@ TEST(CodecDecoder, RetrieveVideoFrameFromDemoMp4)
 	}
 	EXPECT_TRUE(has_nonzero_byte);
 }
+
+TEST(CodecDecoder, ProbeReportsColorTags)
+{
+	const QString path = QDir(QStringLiteral(OAK_TEST_SOURCE_DIR))
+							 .filePath(QStringLiteral("tests/demo.mp4"));
+	ASSERT_TRUE(QFileInfo::exists(path));
+
+	olive::DecoderPtr decoder =
+		olive::Decoder::create_from_id(QStringLiteral("ffmpeg"));
+	ASSERT_TRUE(decoder);
+
+	const olive::FootageDescription desc = decoder->probe(path, nullptr);
+	const QVector<olive::VideoParams> &streams = desc.get_video_streams();
+	ASSERT_FALSE(streams.isEmpty());
+
+	// tests/demo.mp4 is tagged BT.709 primaries and transfer
+	EXPECT_EQ(streams.first().color_primaries(), 1);
+	EXPECT_EQ(streams.first().color_transfer(), 1);
+}