feat(config): add unicode_filenames option to preserve native characters

Add config option to disable ASCII transliteration in filenames, allowing preservation of Korean, Japanese, Chinese, and other native language characters instead of converting them via unidecode.

Closes #49

unshackle/core/config.py

@@ -95,6 +95,7 @@ class Config:
         self.update_check_interval: int = kwargs.get("update_check_interval", 24)
         self.scene_naming: bool = kwargs.get("scene_naming", True)
         self.series_year: bool = kwargs.get("series_year", True)
+        self.unicode_filenames: bool = kwargs.get("unicode_filenames", False)
 
         self.title_cache_time: int = kwargs.get("title_cache_time", 1800)  # 30 minutes default
         self.title_cache_max_retention: int = kwargs.get("title_cache_max_retention", 86400)  # 24 hours default