Normalize CR and CRLF in multi-line strings

[shuheiktgw]

Closes #748

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[Copilot]

Pull Request Overview

This PR addresses the normalization of multi-line strings by converting CR and CRLF to LF, ensuring consistent line breaks.

• Updated the multi-line scanning in scanner/scanner.go to properly handle CR and CRLF sequences.
• Expanded decode_test.go with test cases covering inputs with CR, CRLF, and LF, verifying normalized outputs.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
scanner/scanner.go	Implements CR and CRLF normalization in multi-line strings.
decode_test.go	Adds tests for verifying the normalization of line breaks.

Comments suppressed due to low confidence (2)

scanner/scanner.go:1160

• [nitpick] Consider renaming the variable 'crlf' to 'foundCRLF' for improved clarity on its purpose.

var crlf bool

scanner/scanner.go:1174

• Add an inline comment explaining why subtracting 1 from endPos is necessary when a CRLF is detected, to assist future maintainers in understanding this adjustment.

if crlf { endPos = endPos - 1 }

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.02%. Comparing base (52dacb8) to head (ac837bc).

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Additional details and impacted files

@@            Coverage Diff             @@
##           master     #754      +/-   ##
==========================================
+ Coverage   77.97%   78.02%   +0.04%     
==========================================
  Files          22       22              
  Lines        8108     8126      +18     
==========================================
+ Hits         6322     6340      +18     
  Misses       1370     1370              
  Partials      416      416              

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[shuheiktgw]

I'm not fully confident about this change, since most of the logic is quite similar to what's in the scanNewLine method. I tried to refactor and deduplicate it, but couldn’t come up with a better approach. Open to any suggestions 🙇