* feat: allow custom external port

---------

Co-authored-by: thucpn <thucsh2@gmail.com>

* feat: add selection for vector DB
* feat: add mongo datasource 
* fix: remove not implemented vector dbs

---------

Co-authored-by: Thuc Pham <51660321+thucpn@users.noreply.github.com>

add license
make contextchatengine the default
change git commit message