Update AutoFit option text to prevent wrapping

[justnullname]

Updated the text for the AutoFit option in Settings_Option_AutoFit across all languages to a more compact format. The English version was changed from Auto (100% for small, Fit for large) to Auto (100% / Fit) to prevent text wrapping in the settings menu.

Supported translations (CN, TW, JA, RU, DE, ES) were correspondingly adjusted to shorter strings. Also updated the main.cpp comment related to this option.

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PR created automatically by Jules for task 12693960135130495170 started by @justnullname

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