[FEATURE REQUEST] Support for storing & loading Vector2/Vector2i as stringValues in documents

[xzirox]

Is your feature request related to a problem? Please describe.
Trying to store a Vector2 or Vector2i value to Firestore currently returns an error:
[Firebase Error] >> Action in error was: 2 (UPDATE DOCUMENT)

Describe the solution you'd like
I'd like it to instead be stored as a stringValue and then loaded back as a Vector2 or Vector2i when loaded from the document.

Describe alternatives you've considered
The only alternatives is to manually convert the data to something else before saving it, when it could instead be supported as a built-in type.

[xzirox]

Added support for it.

I should note that my use-case for this is storing player positions in Firestore upon logout and then loading it next time the player goes online.