Move /platform/detection vars into /env (#9707)

* Add platform vars to env

* Replace /platform/detection with /env

src/state/preferences/kawaii.tsx

@@ -1,7 +1,7 @@
 import React from 'react'
 
-import {isWeb} from '#/platform/detection'
 import * as persisted from '#/state/persisted'
+import {IS_WEB} from '#/env'
 
 type StateContext = persisted.Schema['kawaii']
 
@@ -30,7 +30,7 @@ export function Provider({children}: React.PropsWithChildren<{}>) {
   React.useEffect(() => {
     // dumb and stupid but it's web only so just refresh the page if you want to change it
 
-    if (isWeb) {
+    if (IS_WEB) {
       const kawaii = new URLSearchParams(window.location.search).get('kawaii')
       switch (kawaii) {
         case 'true':