Function toChineseYear

Conversion between Arabic numerals and Chinese numeral characters. Supports both financial (大写: 零壹贰) and casual (小写: 〇一二) forms.

toChineseYear(year: number, style?: "upper" | "lower"): string
将年份数字逐位转换为中文数字
Parameters
- year: number
  公历年份，如 2025
- style: "upper" | "lower" = 'upper'
  'upper' 使用〇（日期常用），'lower' 使用零（口语常用）
Returns string
中文数字年份，如 "二〇二五" 或 "二零二五"
Example
```
toChineseYear(2025, 'upper') // "二〇二五"
toChineseYear(2025, 'lower') // "二零二五"
toChineseYear(1900, 'upper') // "一九〇〇"
```
- Defined in chinese-numerals.ts:41