feat(data): SPSC ring buffer, incremental min/max LOD pyramid, series types

tests/CMakeLists.txt

@@ -26,6 +26,9 @@ add_executable(plot_tests
   main.cpp
   test_transform.cpp
   test_gl_context.cpp
+  test_ring_buffer.cpp
+  test_minmax_pyramid.cpp
+  test_series.cpp
   egl_headless.cpp
 )
 target_link_libraries(plot_tests PRIVATE plot::core ${plot_egl_library})