[KM-553] migrate retrieval layer and remove obsolete rag/tools modules

[KM-553] initialize shared contract

initial structure

initial commit

[KM-438][KM-439] Improve Retrieval and Querying feature (#15)

Make a query for tabular (XLSX and CSV) (#14)

Merge dev_new to main (improve retriever and add querying) (#13)

[NOTICKET] fixed single source into multiple sources (#12)

[NOTICKET] add updated_at metadata & prevent duplicate while adding new embedding (#10)

[NOTICKET] add total token logging (#9)

[KM-496] [DED][AI] Fix Response data structure for field sources (db flow)

[NOTICKET] [document]: add doctypes endpoint (#7)

[NOTICKET][DB] add endpoints for dbtypes (#6)

[KM-493] [DED][AI] Fix source extraction in chat

[KM-436][KM-437] add and modify for database and document pipeline (#3)

[NOTICKET] Init db_client endpoint

[KM-467] [DED][AI] Orchestration Agent - Init