Chatlog: Automatically determine regex engine (#7657)
Chatlog: Automatically determine regex engine (#7657)

This makes ripgrep use PCRE2 for searching logs only when necessary.
xfix/Pokemon-Showdown,Zarel/Pokemon-Showdown,xfix/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,svivian/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,xfix/Pokemon-Showdown,sirDonovan/Pokemon-Showdown,svivian/Pokemon-Showdown,svivian/Pokemon-Showdown,svivian/Pokemon-Showdown,xfix/Pokemon-Showdown,Zarel/Pokemon-Showdown,svivian/Pokemon-Showdown,Zarel/Pokemon-Showdown,xfix/Pokemon-Showdown