Redacting usernames in screen recordings: crop plus OCR sweep for tooltips

macOS screen recording filenames contain U+202F (narrow no-break space) before AM/PM, so a typed path with a normal space fails with 'No such file'. Use a glob instead. Cropping the top bar removes the shell prompt and tab-title username, but hover tooltips (e.g. full file paths like /home/<user>/...) can pop up mid-frame for under a second. Run tesseract on frames extracted at about 20fps to find the exact time window. Then use ffmpeg drawbox with t=fill and enable='between(t,a,b)', and re-run the OCR sweep on the output to verify nothing remains.