Integrate SQLite and sqlite-vss extension as another vectorsearch provider

[andreibondarev]

[itsderek23]

Looks like there are 7 providers ... does it make sense to close this for now as 7 feels like enough to support for an eventual 1.0 release?

[aquaflamingo]

Curious if there was any more thought on this? SQLite is growing in support from the Ruby and Rails community at the moment with the new Rails 8 "Solid" approach.

There's been some sponsored work from Mozilla and others with sqlite-vec to enhance SQLite in that way.

Thanks for the great gem!

[CarlQLange]

I have added a PR with some support for sqlite-vec with the caveat that I don't know what I'm doing - all I know is, works on my machine :)

[CarlQLange]

Related sister PR in langchainrb-rails: patterns-ai-core/langchainrb_rails#133