Stats - include match time duration

[donkz]

Is your feature request related to a problem? Please describe. Include real round duration into stats/matchinfo

Describe the solution you'd like Json stats match info should include "duration" property with number of seconds the match lasted exactly

Describe alternatives you've considered I've been taking difference of end and start, but those are raw time values and they may include a pause round_start: "1633111315", round_end: "1633111669", also, sometimes they are 1 second off - like fullhold will be 599 seconds.

Additional context Just for reference - matchinfo json https://rtcwproapi.donkanator.com/matches/16331107772