Debug: Support frame tracing via Tracy

Use CMake FetchContent to pull tracy sources and build it if frame tracing is enabled.
As frame tracing requires annotations in the code, create a wrapper that replaces them
with our own defines that are empty when tracing is not enabled.

main.cpp

@@ -5,6 +5,7 @@
 #include <imgui.h>
 #include <imgui-SFML.h>
 #endif
+#include "FrameTracing.h"
 
 #include "World.h"
 
@@ -37,8 +38,11 @@ int main()
 	sf::Clock frameTime;
 	while (window.isOpen())
 	{
+		FTrace_NamedScope("MainLoop");
+
 		while (window.pollEvent(event))
 		{
+			FTrace_NamedScope("EventLoop");
 			if (event.type == sf::Event::Closed) {
 				window.close();
 				continue;
@@ -135,6 +139,7 @@ int main()
 #endif
 
 		window.display();
+		FTrace_FrameMark;
 	}
 
 #ifdef IMGUI