[NOTICKET] add db_client for querying

[NOTICKET][document]: make a clean output to status error unsupported file type

[NOTICKET] add updated_at field for metadata & delete old embedding before appending

[NOTICKET]: add comments to flag that file type lists must stay in sync

[NOTICKET]: add doctypes endpoint & 10MB file size limit

[NOTICKET] minor code refactor

[NOTICKET][DB] fix mysql pipeline

[KM-437][DB] add mysql, sqlserver, bigquery, snowflake connections

[NOTICKET][DB] menyesuaikan format struktur db_pipeline sesuai dengan file lain

[DB] fix/rename db_pipeline.py

[NOTICKET]: add CSV and XLSX file type

delete duplicate file

[NOTICKET] new metadata format for cleaner code

[KM-441] add mean and median

[NOTICKET][DB] refactor code to new repo

[NOTICKET]: update folder document_pipelines after pipelines

[NOTICKET]: add document pipeline, simplify document API