add SDL3 repository to game engine

examples/asyncio/01-load-bitmaps/README.txt

@@ -1,6 +1,6 @@
-This example code loads a few bitmap files from disk using the asynchronous
-i/o, and then draws it to the window. It uses a task group to watch multiple
-reads and deal with them in whatever order they finish.
-
-Note that for a single tiny file like this, you'd probably not want to bother
-with async i/o in real life, but this is just an example of how to do it.
+This example code loads a few bitmap files from disk using the asynchronous
+i/o, and then draws it to the window. It uses a task group to watch multiple
+reads and deal with them in whatever order they finish.
+
+Note that for a single tiny file like this, you'd probably not want to bother
+with async i/o in real life, but this is just an example of how to do it.