split app.cpp into multiple files, add NodeScroll and use it to scroll the side panels, some fixes to the events system

android/CMakeLists.txt

@@ -36,6 +36,9 @@ add_library(
 	../engine/shader.cpp
 	../engine/shape.cpp
 	../engine/app.cpp
+	../engine/app_events.cpp
+	../engine/app_layout.cpp
+	../engine/app_shaders.cpp
 	../engine/brush.cpp
 	../engine/canvas.cpp
 	../engine/canvas_modes.cpp
@@ -65,6 +68,7 @@ add_library(
 	../engine/node_text.cpp
 	../engine/node_text_input.cpp
 	../engine/node_viewport.cpp
+	../engine/node_scroll.cpp
 )
 
 target_include_directories(native-lib PRIVATE