Add movement relative to time

Previously movement was based on frames rather than
time. I added time_get_dt() function for getting time
since last frame and changed rotation speed to use this
function.

Signed-off-by: Piotr Krygier <piotrkrygier@everyonecancode@xyz>

red_scarf_engine/meson.build

@@ -14,5 +14,8 @@ executable(
   dependencies : [
                   sdl3_dep,
                   ],
-  link_with: rse_graphics_lib,
+  link_with: [
+            rse_graphics_lib,
+            rse_utilities_lib,
+            ],
   )