Add escalation summary generation and product search rejection

Add production features: circuit breaker, exponential backoff, semantic caching, intent-based scope handling

Remove state mutations from scope_validator out-of-scope path

Fix final 3 state mutations: escalation, scope_validator, sanitizer now return partial dicts

Complete state mutation refactor: all nodes now return partial dicts (LangGraph reducer pattern)

Fix interview-critical issues: state mutation anti-pattern, documentation accuracy, prior frustration handling, security notes

Fix critical bugs: compensation for late orders, escalation detection, conversation history improvements

Fix 5 critical bugs: replace LLM scope validator with embedding similarity, add missing state fields, fix routing, improve timeout handling

Add clarification node for missing order IDs + rule-based fallbacks to prevent 504 timeout

Fix contradictory logic: Conditional tone based on delivery timing, frustration threshold 0.5, celebrate early deliveries

Add scope validation and system capabilities: Handle meta queries and reject out-of-scope questions

Fix all 9 critical bugs: API readiness loop, debug params, timeout, LLM cache, state mutation, requirements split, duplicate file

Fix: All 7 critical bugs + 4 security enhancements + compensation policy

Initial commit: Olist intelligence layer with database