Function is_record_start_line 

pub fn is_record_start_line(line: &str) -> bool

判断一行日志是否为记录起始行

验证：时间戳格式 + ( 前缀 + meta 包含 EP、sess、thrd、user、trxid（按序）

use dm_database_parser_sqllog::tools::is_record_start_line;
let valid = "2025-08-12 10:57:09.548 (EP[0] sess:123 thrd:456 user:alice trxid:789 stmt:999 appname:app) SELECT 1";
assert!(is_record_start_line(valid));
assert!(!is_record_start_line("This is not a log line"));