feat(ChatKnowledge):add similarity score and query rewrite

[Aries-ckt]

1. ChatKnowledge

   • add vector recall score threshold(both chroma and milvus)
   • add query rewrite module
     set in .env file

        KNOWLEDGE_SEARCH_REWRITE=True
   

   • add topk details in ChatKnowledge scene

2. Metadata

   • migrate table chat_history and connect_config from duckdb to sqlite and mysql.

execute python script:
duckdb to sqlite

python docker/examples/metadata/duckdb2sqlite.py

duckdb to mysql

1. update your mysql username and password in docker/examples/metadata/duckdb2mysql.py
2.  python docker/examples/metadata/duckdb2mysql.py

3. Add FAQ Documents

Close #849, Close #850, Close #851, Close #852

[csunny]

LGTM