Directions API. Url provider

Description

In terms of Navigation for Android exists 2 types of Navigation(Router), it's Offline and Online. Both of them needs Route-URL provider.(Offline and Online are different modules , have own dependency graph and might be used independent).

Online Router's Route URL is provided by MapboxDirections that is a part of services-core library(under the hood is Retrofit(+OkHttp) library)

Problem

Offline Router cannot consume url from services-core because it brings "network" dependencies like Retrofit and OkHttp(they shouldn't be in Offline navigation).
Offline Router has own route-url provider RouteUrl
The main issue here: two classes where the same piece of logic exist.

Solution

• keep service-core library interfaces as it is
• create additional library (like router-url-provider) that depends on service-directions-model and (if java doesn't have clever approach for creating url) additional java library

How dependency tree looks now

Suggestion

Pros

router-url-provider might be used independently on service-core 👍

cc @mapbox/navigation-android @mapbox/maps-android @mapbox/navigation-api

Start by comparing Router.kt, MapboxDirections.java, and the internal RouteUrl.kt implementation, then inspect the module dependency graphs shown in the issue. Determine how the shared route-URL behavior can be independently consumed without bringing network dependencies into Offline Router; done means both router types can use the shared provider while service-core interfaces remain unchanged.