Fix: move imports and constants for the api-polyfill over from their old location

src/state/lib/api-polyfill.ts

@@ -1,4 +1,7 @@
 import {sessionClient as AtpApi} from '@atproto/api'
+import RNFS from 'react-native-fs'
+
+const TIMEOUT = 10e3 // 10s
 
 export function doPolyfill() {
   AtpApi.xrpc.fetch = fetchHandler