feat(sort): add locale-aware numeric sorting support

Implement NumericLocaleSettings to handle thousands separators and decimal points based on locale. Update tokenization logic to accommodate blank thousands separators for numeric and human-numeric modes, improving parsing of locale-specific numbers. Also refactor numeric locale detection for safety/readability and clean up related initialization/spell-checker ignore.

Author: mattsu2020

src/uu/sort/src/sort.rs

@@ -1330,7 +1330,6 @@ fn detect_numeric_locale() -> NumericLocaleSettings {
     };
     settings
 }
-
 /// Creates an `Arg` for a sort mode flag.
 fn make_sort_mode_arg(mode: &'static str, short: char, help: String) -> Arg {
     Arg::new(mode)