feat: add OutputFile option for log destination in logger

[MyMirelHub]

Description

This PR adds support for writing logger output to a file.

Changes made:

• Added OutputFile to logger options and initialized it in defaults.
• Added a new --log-file CLI flag in AttachCmdFlags.
• Updated ApplyOptionsToLoggers to open the configured file and route logger output to it.
• Added tests for default option values, flag registration, and file-output behavior.

Issue reference

We strive to have all PR being opened based on an issue, where the problem or feature have been discussed prior to implementation.

Please reference the issue this PR will close: #[issue number]

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests

[Copilot]

Pull request overview

Adds support for directing logger output to a user-specified file via a new option/flag, and validates the behavior with unit tests.

Changes:

• Introduces Options.OutputFile and registers a new --log-file CLI flag.
• Updates ApplyOptionsToLoggers to open the configured file and route logger output to it.
• Adds tests covering default values, flag registration, and file-output behavior.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
logger/options.go	Adds OutputFile option + --log-file flag and applies file output in ApplyOptionsToLoggers.
logger/options_test.go	Extends options/flag tests and adds a test that verifies logs are written to the configured file.

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[MyMirelHub]

Follow-up on the review feedback:

• Addressed the FD leak/re-apply behavior by tracking the active log file handle with package-level state + mutex, closing/replacing it on re-apply, and reverting output to stdout when OutputFile is empty.
• Updated file mode from 0600 to 0644 for readable log files.
• Added/kept coverage for re-apply behavior with TestApplyOptionsToLoggersFileOutputReapply.
• Fixed lint follow-ups from CI (noinlineerr, wsl_v5) and re-ran checks.

Latest commit with the lint follow-up: aa1dc88.

Could you please take another look when you have a moment?

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

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[nelson-parente]

@JoshVanL The file handle is tracked and closed — see setLogOutput() in the latest commit (98aedc3):

1. New file opens first
2. All loggers switch to the new output
3. Previous file closes after the switch

// Close the previous log file after loggers have been redirected.
if logOutputFile != nil {
    logOutputFile.Close()
}
logOutputFile = newFile

When OutputFile is empty (or on process shutdown via ApplyOptionsToLoggers with no path), loggers revert to stdout and the file is closed. The logOutputFile + logOutputMu mutex prevent FD leaks across re-applies.