Check if `yt-dlp` is installed and install if necessary.
List available subtitles for the YouTube video.
Attempt to download manual subtitles.
If manual subtitles are unavailable, attempt to download auto-generated subtitles.
If no subtitles are available, prompt the user to transcribe the audio using Whisper.
If Whisper transcription is approved, download the audio and transcribe it.
Post-process the transcript, including deduplication and formatting.
Provide the transcript to the user in the chosen format.