[SDK] Validate and brand the persisted account did (#11387)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

src/screens/Settings/components/DeleteAccountDialog.tsx

@@ -1,6 +1,5 @@
 import {useCallback, useRef, useState} from 'react'
 import {type TextInput, View} from 'react-native'
-import {type DidString} from '@atproto/syntax'
 import {msg} from '@lingui/core/macro'
 import {useLingui} from '@lingui/react'
 import {Trans} from '@lingui/react/macro'
@@ -126,8 +125,7 @@ function DeleteAccountDialogInner({
        */
       await chatClient.call(chat.bsky.actor.deleteAccount)
       await client.call(com.atproto.server.deleteAccount, {
-        // the persisted account did is already resolved
-        did: currentAccount.did as DidString,
+        did: currentAccount.did,
         password,
         token,
       })

src/screens/Settings/components/ExportCarDialog.tsx

@@ -1,6 +1,5 @@
 import {useCallback, useState} from 'react'
 import {View} from 'react-native'
-import {type DidString} from '@atproto/syntax'
 import {Trans, useLingui} from '@lingui/react/macro'
 
 import {saveBytesToDisk} from '#/lib/media/manip'
@@ -34,7 +33,7 @@ export function ExportCarDialog({
     }
     try {
       setLoading('repo')
-      const did = currentAccount.did as DidString
+      const did = currentAccount.did
       const data = await pdsClient.call(com.atproto.sync.getRepo, {did})
       /*
        * getRepo declares `application/vnd.ipld.car`, so lex-client hands back