Add CRLF Support for CSV Exports

Description

This PR adds support for Windows-style line endings (CRLF) in CSV exports, while maintaining the default UNIX-style line endings (LF). This enhancement improves compatibility with Windows-based systems and tools that expect CRLF line endings.

Changes

• Added line_ending configuration option to CSV writers with two possible values:
  • lf (default): Uses UNIX-style line endings
  • crlf: Uses Windows-style line endings
• Updated both CsvWriter and ArrowToCsvWriter to support line ending configuration
• Added comprehensive test coverage for both line ending types
• Updated documentation to reflect the new configuration option

Technical Details

• Added CsvLineEnding type to configuration specs
• Implemented custom CSV dialect for Python's csv writer to handle CRLF
• Added version-aware implementation for PyArrow CSV writer (supports line endings from version 14.0)
• Added configuration options in both TOML and environment variables

Testing

• Added unit tests for both CsvWriter and ArrowToCsvWriter
• Verified correct line ending generation for both LF and CRLF
• Ensured no mixed line endings in output files
• Added tests for both direct data writing and Arrow table conversion

Documentation

• Updated CSV format documentation to include the new line_ending option
• Added examples for both TOML and environment variable configurations

Configuration Example

[NORMALIZE]
data_writer__line_ending="crlf"

Or via environment variable:

NORMALIZE__DATA_WRITER__LINE_ENDING=crlf

Checklist

• Added new configuration option
• Implemented support in both CSV writers
• Added comprehensive tests
• Updated documentation
• Verified backward compatibility
• Added examples for configuration