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

Clone-Video.ps1

@@ -898,7 +898,7 @@ if (-not [string]::IsNullOrWhiteSpace($Sequence)) {
         '-y'
         '-i', $SourcePath
         '-vf', $videoFilter
-        '-vsync', 'vfr'
+        '-fps_mode', 'vfr'
         '-frames:v', '1'
         '-q:v', '1'
         '--', $SequencePath
@@ -984,7 +984,7 @@ if ($StartFrame -gt 0 -or $actualEndFrame -lt $maxFrameIndex) {
     $videoFilter = $filterParts -join ','
     $ffmpegArgs += @(
         '-vf', $videoFilter
-        '-vsync', 'vfr'
+        '-fps_mode', 'vfr'
     )
     $ffmpegArgs += $targetVideoEncodeArgs
     if ($CRF -ge 0) {