Claude Code: idle chats now compact before the cache expires

Leave a 200K+ token terminal chat alone ~54 minutes and it compacts itself before the one-hour prompt cache dies — so your next message doesn’t re-chew the whole transcript. Tune with CLAUDE_CODE_IDLE_COMPACT_MIN_TOKENS or kill it with "idleCompaction": false. Also: CLAUDE_CODE_DISABLE_FILE_MENTIONS (paths only, not file guts), and OTel now splits cache writes into cache_creation_5m_tokens / cache_creation_1h_tokens.