Fix leftover output files and file handle leak when extraction fails

[alek-prykhodko]

Summary

When file or resource fork extraction fails (due to a wrong password, cancellation, etc.) the output file created before extraction started was left on disk as empty or partial.
Additionally, a failed AppleDouble header write in _extractResourceForkEntryWithDictionary:asAppleDoubleFile: returned early without calling [fh close], leaking the file handle.

Changes

• _extractFileEntryWithDictionary:as: — remove the output file on any non-zero error after [fh close];
• _extractResourceForkEntryWithDictionary:asAppleDoubleFile: — unify the error path so [fh close] always runs, and remove the output file on any non-zero error.

P.S. Both fixes removes files for XADBreakError as well — cancellation is checked per 256KB chunk inside the read loop, so the file is partial in most cases at that point.

[Copilot]

Pull request overview

This PR improves extraction failure handling in XADUnarchiver by ensuring partially created output files are cleaned up and a file-handle leak is avoided when AppleDouble header writing fails.

Changes:

• Delete the destination file after extraction when _extractFileEntryWithDictionary:as: returns a non-zero XADError.
• Refactor _extractResourceForkEntryWithDictionary:asAppleDoubleFile: to consolidate error handling so the file handle is always closed.
• Delete the AppleDouble output file on any non-zero XADError from header writing or resource-fork extraction.

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[PaulTaykalo]

Fix removes leftover output files and a file-handle leak when extraction fails. Author shipped XADMasterTests/Stuffit/StuffitTests.m::testExtractionWithWrongPasswordDoesNotLeaveFilesOnDisk covering the primary path with the 1234567.sit.bin fixture. The resource-fork (AppleDouble) error path is unchanged in behavior but untested; suggested follow-up, not blocking.