Exported files have timestamp/time-code as embedded subtitle.

[beeepus]

Describe what you are trying to accomplish and why in non technical terms
Have timestamp/time-code (date & time) as soft subtitle embedded in the exported files.

Describe the solution you'd like
ffmpeg have the option to merge subtitle in to the file, no re-encoding.
Command example
ffmpeg -i video.mp4 -i subs.srt -c copy -c:s mov_text output.mp4

frigate need to feed the time-code in to the exported file some how.

Describe alternatives you've considered

Additional context