Function getWeekdayName

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

getWeekdayName(weekday: number, locale?: string): string
获取星期几名称
Parameters
- weekday: number
  0-6 (0=周日, 1=周一, ..., 6=周六)
- locale: string = 'zh-CN'
  地区代码（默认 'zh-CN'）
Returns string
星期几名称
Example
```
getWeekdayName(0, 'zh-CN')  // "星期日"
getWeekdayName(6, 'zh-CN')  // "星期六"
getWeekdayName(6, 'ja-JP')  // "土曜日"
getWeekdayName(6, 'ko-KR')  // "토요일"
getWeekdayName(6, 'vi-VN')  // "Thứ Bảy"
```
- Defined in chinese-numerals.ts:108