Updated structure and field names for consistency

Type names are camel case and field names are snake case except for fields ending in id, which are capitalized.

Fixes https://github.com/libsdl-org/SDL/issues/6955

include/SDL3/SDL_oldnames.h

@@ -492,6 +492,9 @@
 /* ##SDL_timer.h */
 #define SDL_GetTicks64 SDL_GetTicks
 
+/* ##SDL_version.h */
+#define SDL_version SDL_Version
+
 /* ##SDL_video.h */
 #define SDL_GetClosestDisplayMode SDL_GetClosestFullscreenDisplayMode
 #define SDL_GetDisplayOrientation SDL_GetCurrentDisplayOrientation
@@ -961,6 +964,9 @@
 /* ##SDL_timer.h */
 #define SDL_GetTicks64 SDL_GetTicks64_renamed_SDL_GetTicks
 
+/* ##SDL_version.h */
+#define SDL_version SDL_version_renamed_SDL_Version
+
 /* ##SDL_video.h */
 #define SDL_GetClosestDisplayMode SDL_GetClosestDisplayMode_renamed_SDL_GetClosestFullscreenDisplayMode
 #define SDL_GetDisplayOrientation SDL_GetDisplayOrientation_renamed_SDL_GetCurrentDisplayOrientation