Fixed marathon best saving logic + marathon results UI (#768)

Getting a new best in marathon mode that doesn't shave off a second of time (i.e. if you went from a time of 17.54 to 17.10) will no longer be internally ignored and now gets properly saved. Along with that, the world select menu now uses the proper marathon tracker icons.

Scenes/Prefabs/UI/MarathonResults.tscn

@@ -175,6 +175,7 @@ offset_right = 90.0
 offset_bottom = 32.5
 grow_horizontal = 2
 grow_vertical = 2
+has_speedrun_stuff = true
 
 [node name="LevelSelect" parent="." instance=ExtResource("8_orie5")]
 visible = false

Scripts/Classes/Singletons/SpeedrunHandler.gd

@@ -303,7 +303,7 @@ func run_finished() -> void:
 	if Global.current_game_mode == Global.GameMode.BOO_RACE:
 		pass
 	else:
-		var best := -1
+		var best: float = -1
 		if Global.current_game_mode == Global.GameMode.MARATHON_PRACTICE:
 			if is_warp_run:
 				best = best_level_any_times.get(str(Global.world_num) + "-" + str(Global.level_num), -1)
@@ -314,7 +314,6 @@ func run_finished() -> void:
 				best = marathon_best_any_time
 			else:
 				best = marathon_best_warpless_time
-		
 		if best <= 0 or best > timer:
 			if Global.current_game_mode == Global.GameMode.MARATHON_PRACTICE:
 				save_recording()