WhatsApp bridge (bridge.js) only sets ptt:true when file extension is .ogg
or .opus, causing mp3/wav files (from Edge TTS, NeuTTS, etc.) to arrive
as file attachments instead of voice bubbles — silently, with no error.
Fix: when audio type is sent with a non-ogg/opus format, run ffmpeg
conversion to ogg/opus in a temp file before sending. This makes
send_voice() self-sufficient regardless of what format the caller provides.
Fallback: if ffmpeg is unavailable, original buffer is sent (previous
behaviour) with a console.warn — no crash.
Addresses veloguardian's review comment on PR #4992.
dad62c4c47