Function parse_thai_date 

pub fn parse_thai_date(text: &str) -> Option<ThaiDate>

Parses a Thai date string into a ThaiDate.

Returns None if the input cannot be recognized as a valid date.

use kham_core::date::{parse_thai_date, Era};

let d = parse_thai_date("๕ ก.ค. ๒๕๖๗").unwrap();
assert_eq!(d.day, 5);
assert_eq!(d.month, 7);
assert_eq!(d.year, 2567);
assert!(matches!(d.era, Era::Buddhist));