refactor(machine_a_trier): update adaptive difficulty to level-based streaks

[Animation-EdNum]

This change introduces level-based streak logic in the "Sorting Machine" (machine_a_trier.html) application. Previously, the ScoreManager's default behavior would aggressively suggest bumping up the difficulty based solely on consecutive correct item drops.

Now, the game only suggests progressing to the next difficulty level if the player perfectly sorts all items in an entire level without a single mistake, two times in a row.

Changes:

• Added perfectLevelsStreak and mistakesInCurrentLevel variables.
• Disabled the default ScoreManager.checkAdaptiveDifficulty to prevent per-item popups.
• Reset the streak variables appropriately upon starting new levels or changing game modes.
• Fixed the c2_change_difficulty event listener so that the adaptive popup correctly registers easy, medium, and hard transitions instead of referencing numerical keys.

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PR created automatically by Jules for task 14341640135608460403 started by @Animation-EdNum

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