v2.3 — Async RAG + Telemetry + Anti-Abuse Shield

v2.3 — Production-Grade RAG Upgrade

New Features

• Async Streaming: True async _arun() with asyncio.to_thread — no event loop blocking
• Multi-Query RRF: 3 sub-query expansion + Reciprocal Rank Fusion (k=60) with multi-level tiebreaker
• SQLite Caching: Isolated 5-minute TTL cache — bypasses BM25 on repeat queries
• Telemetry: Automatic search latency + cache hit-rate tracking (.cache/langchain_telemetry.db)
• Anti-Abuse Shield: Sliding window audit — rate limit (10 queries < 2s) and low quality (hit-rate < 10%) circuit breaker

Agent Ecosystem

• 6 external contributors, 0 bounty payout
• ~800 lines production code, ~260 lines tests, 4 lessons
• Auto PR audit via pr-checks.yml (pytest + coverage + comment)

Infrastructure

• Registration Worker: counter auto-increment + welcome comment + input sanitization
• Frontend: 30s localStorage cache, tab-focus refresh, cache-busting params
• CI: All 7 workflows have explicit permission blocks (CodeQL clean)