in mixed log dir, lines can be missed if multiple files are frequently updated

[ftc2]

currently, there is a single log_parse() thread parsing the newest file, and when log_scan() finds a newer file, it sends a termination signal to the old log_parse() before spawning a new one.

in mixed log dir situation, if multiple files are being frequently updated, lines can be missed if the log_scan() thread doesn't switch to the new log fast enough (rn it scans for newer file every 1s).

having log_scan() make a separate log_parse() thread for each log file present (and adding new threads as new files appear) could be better i guess?

[ftc2]

not ideal, but probably less of an issue now with increased polling frequency (look for newer log every 0.5s, read lines every 0.1s)