[FEAT] Mirrored Game Mode

[jotaefepinho]

This PR implements the sub-issue in #380. It's still being worked on. It implements:

• [FEAT] Add "Mirrored" game mode option to UI
• [FEAT] Implement collision rules for Mirrored mode
• [FEAT] Implement mirrored growth and scoring

[ghtormena]

great job! it seems pretty clear to me :)

[DeguShi]

@jotaefepinho @bruno-lim4 The mirrored snakes can cross/overlap the board because there's no position mirroring, only input mirroring. Both snakes move independently using the same wrapping logic. I recommend adding actual position constraints to keep the snakes mirrored. Another thing I noticed is that the start position of the snakes is only properly mirrored when I use odd-sized grids; however, the frontal collision seems to happen before the actual collision then (might be visual lag, not sure). The screen recording below was taken from a 16×16 grid:

Screen.Recording.2025-12-04.at.10.26.32.mov

Apart from that, it would be interesting to rebase the branch, as many changes seem to have been merged into dev compared to what the branch currently has.

[LeticiaBN]

The game is working fine now, you fixed the bugs @DeguShi mentioned. Very good game mode!!

Please rebase the PR before I approve: there are conflicts with some files that were updated in dev

[DeguShi]

Like @LeticiaBN said, as soon as the conflicts are resolved I will approve the merge. The game mode is great, good job!

[jotaefepinho]

The code is apparently working now. Small heads-up: Mirrored mode must have an even-sized grid, otherwise some positions become unreachable.

[DeguShi]

looks great! congrats

He has fixed everything