This commit adds multiple major features and improvements:
1. Adds Milvus vector database configuration and client integration
2. Implements daily summary query API for customer chat records
3. Adds customer statistics calibration functions, including single and full recalculation
4. Optimizes session list merging logic to handle bidirectional session IDs
5. Adds new mapper methods for customer message statistics query
6. Fixes message statistics update logic to avoid duplicate counting
7. Adds daily scheduled task to reset customer daily message count
8. Adds frontend page for viewing customer daily summaries
