not use global vars anymore & other fixes

in tictactoe game / snake / arkanoid

applications/arkanoid/application.fam

@@ -5,6 +5,6 @@ App(
     entry_point="arkanoid_game_app",
     cdefines=["APP_ARKANOID_GAME"],
     requires=["gui"],
-    stack_size=3 * 1024,
+    stack_size=4 * 1024,
     order=30,
 )