MazeWeb UIDesync: Player position temporarily resets visually when new participant joins

[abelshinev]

Observed:
When a new participant joins, existing players' positions appear to reset to a default location.
However, actual state is preserved, and position snaps back on next movement.

Impact:
This creates inconsistency between UI and actual game state, which can confuse users and appear as progress loss.

Expected:
UI should remain consistent with the actual player position when new participants join.

sugarizer-recording.2.mp4

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Steps to reproduce:

1. Start shared MazeWeb session with User A and B
2. Move players to different positions
3. User C joins session

[llaske]

I don't think it's an issue, it's just possible to play with several users on the same screen using different keyboard.
See https://github.com/llaske/sugarizer/blob/dev/activities/MazeWeb.activity/js/activity.js#L140