Log languages a post is tagged with after translating (#10014)

Co-authored-by: Eric Bailey <git@esb.lol>

src/components/dms/MessageContextMenu.tsx

@@ -1,5 +1,5 @@
 import {memo, useCallback} from 'react'
-import {LayoutAnimation} from 'react-native'
+import {LayoutAnimation, Platform} from 'react-native'
 import * as Clipboard from 'expo-clipboard'
 import {type ChatBskyConvoDefs, RichText} from '@atproto/api'
 import {msg} from '@lingui/core/macro'
@@ -67,6 +67,7 @@ export let MessageContextMenu = ({
     void translate(message.text, langPrefs.primaryLanguage)
 
     ax.metric('translate', {
+      os: Platform.OS,
       sourceLanguages: [],
       targetLanguage: langPrefs.primaryLanguage,
       textLength: message.text.length,