Add `toasty-mongodb`

[bsodmike]

This could be quick given there is toasty-dynamodb already, but the underlying crates would need to be changed.

[nikhil-pandey]

+1

[JJPuck]

We have a library very similar to toasty at work that we've considered open sourcing. It primarily targets mongodb. If there's interest I could look at porting it across, though it uses derive macros rather than code generation ahead of time.

[itsparser]

@JJPuck are you working on this Issue right now

[JJPuck]

I started working on it but took a brief pause while the derive macros got pulled in and then got slammed by work and haven't had time. Hoping to get back to it in a few weeks

[kumarUjjawal]

@JJPuck what's the status of this?