feat(dashboard): Update v2 store domain to follow conventions, and abstract some logic (#6927)

**What**
- Updates the V2 store domain.
- Abstracts some of the API requests logic into re-usable hooks

**Note**
- Partial PR as we need to add support for setting a default currency, region and location. Currently the `q` param is missing on all V2 endpoints, so we can't use our combobox component to list these options. Will be added later when that has been fixed in core.
- The PR includes a generic hook for fetching combobox data, that I added before realising that `q` is not currently supported. But keeping it as it will be useful once support is added.

packages/admin-next/dashboard/src/providers/router-provider/v2.tsx

@@ -5,10 +5,9 @@ import { SettingsLayout } from "../../components/layout/settings-layout"
 import { Outlet } from "react-router-dom"
 
 import { Spinner } from "@medusajs/icons"
+import { SalesChannelDTO, UserDTO } from "@medusajs/types"
 import { ErrorBoundary } from "../../components/error/error-boundary"
 import { useV2Session } from "../../lib/api-v2"
-import { SalesChannelDTO } from "@medusajs/types"
-import { UserDTO } from "@medusajs/types"
 import { SearchProvider } from "../search-provider"
 import { SidebarProvider } from "../sidebar-provider"
 
@@ -135,7 +134,7 @@ export const v2Routes: RouteObject[] = [
                 lazy: () => import("../../v2-routes/store/store-edit"),
               },
               {
-                path: "add-currencies",
+                path: "currencies",
                 lazy: () =>
                   import("../../v2-routes/store/store-add-currencies"),
               },