fix(io): honor CRLF option when saving text files in save()

[Pcmhacker-piro]

Description

Resolves #9141

Root Cause

When calling save() on text / string arrays:

1. save() delegated to fn.saveStrings(args[0], args[1], args[2]) without passing args[3] (isCRLF), discarding the CRLF option when passed as save(data, 'filename', 'txt', true).
2. When the extension is included in the filename parameter (e.g. save(data, 'filename.txt', true) or saveStrings(data, 'filename.txt', true)), _checkFileExtension extracts the 'txt' extension, and the boolean flag was passed as args[2]. saveStrings(list, filename, extension, isCRLF) received extension = true and isCRLF = undefined, defaulting to LF (\n).

Changes

• Updated fn.save() to forward args[3] to fn.saveStrings(args[0], args[1], args[2], args[3]).
• In fn.saveStrings(), check if (typeof extension === 'boolean') { isCRLF = extension; extension = undefined; } so passing (list, 'filename.txt', true) properly sets isCRLF = true.
• Added unit tests in test/unit/io/files.js verifying CRLF output for both save() (4-argument and 3-argument signatures) and saveStrings() (extension omitted).

Proof & Verification

Real Terminal Video (asciinema recording)

Unit Tests Passing

PR Checklist

• npm run lint passes
• npx vitest run test/unit/io/files.js passes (all 21 unit tests pass)
• No breaking API changes introduced

[Pcmhacker-piro]

Hi @ksen0 @limzykenneth, could you please review this PR when you get a chance? It resolves #9141 by ensuring the CRLF parameter is respected in save() and saveStrings(). Real terminal asciinema recording, passing unit tests, and lint checks have been verified and attached. Thank you!