Build with FFMPEG broke --diarize support on server mode

[slavonnet]

Found bug

If build with FFMPEG, run server with --diarize and try send stereo file - server can't read file If build with FFMPEG, run server with --diarize--convert and try send stereo file - server return (speaker ?) If build without FFMPEG, run server with --diarize and try send stereo file - server return correct speakers

[opsec-ai]

Need to separate arguments with space. --diarize --convert

The error message, "Received request: /tmp/tmp8y9c3cb9.wav Couldn't open input file RIFF$ error: failed to ffmpeg decode 'RIFF$' error: failed to read audio data"

is not very friendly though!

The correct behavior would be for the ffmpeg-enabled server to avoid using ffmpeg on wav files. Or if it must use ffmpeg, then always use it (and eliminate the --convert flag).