[Session] Add useAgent hook and replace (#3706)

* Hook it up

* Memoize getAgent method

* Use one shared reference

---------

Co-authored-by: Dan Abramov <dan.abramov@gmail.com>

src/state/queries/my-lists.ts

@@ -3,7 +3,7 @@ import {QueryClient, useQuery} from '@tanstack/react-query'
 
 import {accumulate} from '#/lib/async/accumulate'
 import {STALE} from '#/state/queries'
-import {getAgent, useSession} from '#/state/session'
+import {useAgent, useSession} from '#/state/session'
 
 export type MyListsFilter =
   | 'all'
@@ -16,6 +16,7 @@ export const RQKEY = (filter: MyListsFilter) => [RQKEY_ROOT, filter]
 
 export function useMyListsQuery(filter: MyListsFilter) {
   const {currentAccount} = useSession()
+  const {getAgent} = useAgent()
   return useQuery<AppBskyGraphDefs.ListView[]>({
     staleTime: STALE.MINUTES.ONE,
     queryKey: RQKEY(filter),