New installs start detecting instead of being locked to one language; a stored
value from before this default still wins. The dictation chain asks
transcribe_detected() in auto mode, records the detected code in history as
speech_language, hands it to the cleanup prompt (a detected Turkish recording
gets the Turkish prompt and glossary rule), and reports it on the socket reply.
The stale comment claiming whisper.cpp's -l auto does not detect is corrected.