Upload 404 warning doc_set(merge=True) in upload.py — creates doc if missing
MQTT call_end 404 error doc_set(merge=True) in mqtt_handler.py — same root cause
Transcription 404 (saving transcript to nonexistent doc) doc_set(merge=True) in transcription.py
Transcription ADC credentials error Explicit service_account.Credentials from gcp-key.json in _sync_transcribe — same pattern as storage.py
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