Refactor summarize_all to run LLM summarization across a thread pool (default 8
workers) while keeping all SQLite reads/writes on the main thread (the single
connection is never shared across threads). Extract _summarize_transcript
(transcript -> gist, no DB) for the worker.
The MI50 proved far too slow for the large-transcript backfill (~29 summaries in
9h due to gfx906 prefill); on cloud gpt-4o-mini with concurrency this runs at
~30 summaries/minute (~17 min for the full backfill, ~$2). MI50 stays the chat
backend where small prompts make it snappy.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
serversdown
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