feat: add allowSymlinks option to File transport for symlink handling

[omdxp]

This PR adds a new option allowSymlinks to the File transport to give users control over whether symbolic links should be followed when writing logs.

[Copilot]

Pull request overview

This PR adds a new allowSymlinks option to the File transport to control whether symbolic links should be followed when writing logs. When set to false, the transport uses the O_NOFOLLOW flag to prevent writes to symlinks, enhancing security by preventing symlink-based attacks.

Key Changes:

• Added allowSymlinks option (defaults to true for backward compatibility)
• Modified stream creation to use O_NOFOLLOW flag when symlinks are disallowed
• Added comprehensive test coverage for both enabled and disabled symlink handling

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 6 comments.

File	Description
lib/winston/transports/file.js	Adds allowSymlinks option initialization and implements O_NOFOLLOW flag logic in _createStream method
test/unit/winston/transports/file.test.js	Adds new test suite "Symlink Option" with tests for both allowSymlinks: false and default behavior

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[indexzero]

👍 once the workflow runs pass

[omdxp]

@indexzero I've pushed additional tests to improve coverage and potentially resolve the pipeline failure