fix(manifest): validate backup inventory before marking files missing

docs/ios/records.md

@@ -206,6 +206,8 @@ If indicators are provided through the command-line, they are checked against th
 
 An incomplete backup still lists in its manifest the files it failed to acquire. Those records carry a `"missing": true` field, and the module reports how many of them it found. Use it to tell a module which returned nothing because the artifact was not acquired apart from one which found nothing on a device that never had it.
 
+Files must be stored at their expected paths inside the backup folder. If the module cannot finish listing the backup files, it logs a warning and skips the missing-file check; the manifest metadata is still extracted.
+
 ---
 
 ### `os_analytics_ad_daily.json`