Add Packages to Pro API, and a few Typing Enhancements

[macserv]

Pro Package API

• Add Pro API Package model.
• Add ProApi.get_packages_v1() with overloads.
• Add allowed sort & filter fields for Package request.
• Update documentation for Package model.
• Add integration tests for Package model.

Typing Enhancements

• Add files parameter to pro_api_request() (create policies with icons!)
• Add overloads for get_computer_inventory_v1().
• Resolve type-checking issues when package is installed as editable.
• Resolve several other miscellaneous type-checking issues.

[brysontyrrell]

Can you discuss the inclusion of overloads? I'm not seeing the value they're bringing to the two interfaces you've implemented them with.

[macserv]

Sure! It allows the type checker to infer what will be returned by the method, based on whether or not pagination is being used. This doesn't do much within the API itself, but it improves the ergonomics of code that consumes the SDK.

[brysontyrrell]

Sure! It allows the type checker to infer what will be returned by the method, based on whether or not pagination is being used. This doesn't do much within the API itself, but it improves the ergonomics of code that consumes the SDK.

Not two minutes after I sent that did it click that it made the return type deterministic.

...I am not against this. I'd want to get it added to the remaining Pro API methods though and included in the dev docs as a part of the style guide.

[brysontyrrell]

This is an overall very solid PR with good enhancements. 🎉

[macserv]

I'd want to get [overloads] added to the remaining Pro API methods…

Overloads added to other Pro API methods.

[macserv]

I'd want to get [overloads] … included in the dev docs as a part of the style guide.

Updated contributors/index.rst to specify that @overload interfaces should be provided for methods with dynamic return types. Also added recommendation to use Optional[] for types where value can be None.