Replace deprecated -vsync flag with -fps_mode in Clone-Video.ps1 and Get-FramesRange.ps1 frame extraction commands to use current ffmpeg syntax while maintaining vfr (variable frame rate) behavior

Get-FramesRange.ps1

@@ -148,7 +148,7 @@ for ($frameIndex = $startFrame; $frameIndex -le $endFrame; $frameIndex++) {
         '-y'
         '-i', $VideoPath
         '-vf', $videoFilter
-        '-vsync', 'vfr'
+        '-fps_mode', 'vfr'
         '-frames:v', '1'
         '-q:v', '1'
         '--', $outputFile