[go_router] Expose full Uri on GoRouterState in GoRouterRedirect - #5742

A number of developers have voiced the desire to be able to know whether a GoRouterState is the result of a deep-link or in-app navigation from within their GoRouter's redirect method. This can be accomplished by exposing the Uri's scheme and host on the GoRouterState. This way, we can know whether the GoRouterState is the result of a deep-link by checking state.uri.scheme != null or state.uri.host != null.

This PR would close #103659.

No tests were broken as a result of this change, and we have added coverage for this change through new tests.

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