fix: improve binary content detection and null byte handling

[aeromomo]

• Add binary content detection based on null byte percentage (>5%)
• Add control character validation to avoid processing binary files as text
• Remove null bytes from decoded text content to prevent downstream issues
• Add logging for binary content detection and null byte removal

This prevents potential issues when processing files that contain null bytes or other binary data that could cause problems in text processing pipelines.

The fix uses a 5% threshold for null bytes to distinguish between text files with occasional null bytes and truly binary content.

Description

Related Issue

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test update

Changes Made

Testing

• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have tested this on the following platforms:
  • Linux
  • macOS
  • Windows

Checklist

• My code follows the project's coding style
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Screenshots (if applicable)

Additional Notes

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