WIP: fix(document): allow validation of moddelless documents on node side

[captaincaius]

Hi - this PR is incomplete because it lacks tests, docs, etc. because I wanted to see if you're okay with this approach first. To me it improves DX and is also a little more maintainable b/c it makes the code paths the same on the client-side and server-side with respect to non-persistent documents.

If you're okay with this direction, please let me know if you have a better idea for a name than "ephemodel" (ephemeral model) :-/.

Fix #8237, fix #8272, and improve DX by making ephemeral models similar
to normal ones

Summary

This fixes modelless document validation on the server-side by sharing its exact same code path with that of browser-side documents.

Browser-side syntax is currently broken on the server-side, so making models for DTO-type sanitizers can currently only be done by making a REAL model.

Examples

const Ephey = goosey.ephemodel(new goosey.Schema({hair: Number}));
const dockey = new Ephey({hair: 'red', eyes: 'green'});
console.log(dockey.validateSync());
console.log(dockey.toObject());

...prints...

{ ValidationError: Validation failed: hair: Cast to Number failed for value "red" at path "hair"
...and...
{}

[vkarpov15]

I'm not sure I can support this approach because I really don't want to import browser document into node code. If the only issue is what you saw in #8272, that's a pretty easy fix.

[captaincaius]

Thanks for the quick review.

Okay... I had a hunch you'd say that, so I'm glad I didn't get too elaborate with it. I'll close this.

FWIW, I was going to rename browserDocument because a databaseless document is useful beyond the browser, but never mind.

Thanks again.

[vkarpov15]

Yeah 'databaselessDocument' is overkill since the Document class is databaseless anyway :) The reason why mongoose's Model class inherits from the Document class is that Document is intended to hold all the db-independent stuff: validation, etc. Model has everything that actually requires a database connection.