Install and use the speechall CLI tool for speech-to-text transcription. Use when the user wants to: (1) transcribe audio or video files to text, (2) install speechall on macOS or Linux, (3) list available STT models and their capabilities, (4) use speaker diarization, subtitles, or other transcription features from the terminal. Triggers on mentions of speechall, audio transcription CLI, or speech-to-text from the command line.