Add platform support note and existing file handling documentation to README and skill docs, clarifying Windows 11-only testing, per-script ffmpeg/ffprobe requirements, and file replacement behavior with -y flag across Clone-Image.md, Clone-Video.md, Compare-Videos.md, Crop-Clips.md, Get-VideoAudio.md, SKILL.md and index.md

skill/Get-VideoAudio.md

@@ -53,7 +53,12 @@ Extracts audio in either WAV or MP3 format from a video file.
 - If the video file has no audio stream, the script displays a message and exits without creating an output file
 - WAV format uses PCM 16-bit encoding (lossless)
 - MP3 format uses 320 kbps bitrate (highest quality)
-- If output file already exists, it will be overwritten
+
+## Existing Files
+
+- An existing output file, the default `<video>.wav` or `<video>.mp3`, or the `-Output` path, is **replaced** without a prompt. ffmpeg runs with `-y`, so the old file is lost. Use `-WhatIf` first, or write to a new name.
+- If the output folder does not exist, ffmpeg fails and the script stops with an error.
+- If the video has no audio stream, the script prints a message and exits successfully. It creates no file and leaves any existing output untouched.
 
 ## Safe Execution