[Uri] Consider adding query string manipulation

[paulomorgado]

Web APIs are everywhere these days and there's still no way to manipulate them in the framework.

System.Web has one. System.ServiceModel has another. And pretty much every library that needs it has one.

It would be nice to have something that:

• Parses a query string into a NameValueCollection.
• Allows manipulating the values
• Renders que query string

[karelz]

Triage:
@paulomorgado which types exist in System.Web and System.ServiceModel?
We should consider extending UriBuilder.

@paulomorgado what kind of value manipulation do you need and why?

[paulomorgado]

In System.Web you can find System.Web.HttpValueCollection.

If HttpValueCollection was public and all it's issues were fixed, it could be used besides UrlBuilder like it is on System.Web.

Or maybe it's a set of parsing and rendering extension methods on NameValueCollection would be enough.

[MihaZupan]

Closing in favour of #32606