Player should keep direction when horizontal speed is zero

Consider that a player has an ability to turn. For easier reproduction, here's a patch that allows this from the start:
```
Index: O21.Game/Engine/Entities.fs
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/O21.Game/Engine/Entities.fs b/O21.Game/Engine/Entities.fs
--- a/O21.Game/Engine/Entities.fs (revision Staged)
+++ b/O21.Game/Engine/Entities.fs (date 1746995143324)
@@ -115,7 +115,7 @@
Direction = Right
Lives = GameRules.InitialPlayerLives
Score = 0
- Abilities = Array.empty
+ Abilities = [| { Type = AbilityType.AllowTurn; Lifetime = 0 } |]
Oxygen = OxygenStorage.Default
}
and OxygenStorage = {

```

Now, the player presses keys `Left`, `Right`.

In the original, this leads to horizontal speed of zero but still left-turning position,

In O21 currently, it leads to right-turning position (the default one).

It should keep the player sprite to face left.