Update for SDL3 coding style (#6717)

I updated .clang-format and ran clang-format 14 over the src and test directories to standardize the code base.

In general I let clang-format have it's way, and added markup to prevent formatting of code that would break or be completely unreadable if formatted.

The script I ran for the src directory is added as build-scripts/clang-format-src.sh

This fixes:
#6592
#6593
#6594

(cherry picked from commit 5750bcb174)

test/testnativex11.c

@@ -38,14 +38,14 @@ CreateWindowX11(int w, int h)
         XMapRaised(dpy, window);
         XSync(dpy, False);
     }
-    return (void *) window;
+    return (void *)window;
 }
 
 static void
 DestroyWindowX11(void *window)
 {
     if (dpy) {
-        XDestroyWindow(dpy, (Window) window);
+        XDestroyWindow(dpy, (Window)window);
         XCloseDisplay(dpy);
     }
 }