feature: sqlite extensions

[barraguda]

Is your feature request related to a problem? Please describe.
vector search in sqlite could be cool, there are many extensions that do this

Describe the solution you'd like
Be able to load sqlite extensions into a specific database.

Describe alternatives you've considered
Add basic built in ones?

impl

add an SqliteAction type LoadExtension { file: String/bytes, entrypoint: Option<String> }

ref: https://www2.sqlite.org/cvstrac/wiki?p=LoadableExtensions

Notes

..security?