fix(core):The writeContentToFile error message now includes allowed paths, Show allowed paths in file write error message

[vinay02022]

Summary

• Improved writeContentToFile error message to include allowed paths when file access is blocked
• Aligns behavior with createReadStream which already shows allowed paths in its error message
• Helps users understand why file access is blocked and how to configure N8N_RESTRICT_FILE_ACCESS_TO

Related Linear tickets, currentMilestone issues, or community forum posts

#23934

Review / Merge checklist

• PR title and target branch are correct
• Tests verify the change works as intended
• Docs updated if needed

Before: The file "/files/output.txt" is not writable.

After: The file "/files/output.txt" is not writable. Allowed paths: /home/user/.n8n-files

[CLAassistant]

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[cubic-dev-ai]

No issues found across 3 files

[n8n-assistant]

Hey @vinay02022,

Thank you for your contribution. We appreciate the time and effort you’ve taken to submit this pull request.

Before we can proceed, please ensure the following:
• Tests are included for any new functionality, logic changes or bug fixes.
• The PR aligns with our contribution guidelines.

Regarding new nodes:
We no longer accept new nodes directly into the core codebase. Instead, we encourage contributors to follow our Community Node Submission Guide to publish nodes independently.

If your node integrates with an AI service that you own or represent, please email [email protected] and we will be happy to discuss the best approach.

About review timelines:
This PR has been added to our internal tracker as "GHC-6194". While we plan to review it, we are currently unable to provide an exact timeframe. Our goal is to begin reviews within a month, but this may change depending on team priorities. We will reach out when the review begins.

Thank you again for contributing to n8n.