Bug: binary symbols appear in code-slicer output

[sobeaa]

Bug: binary symbols appear in code-slicer output

code-slicer can sometimes output unreadable binary-looking symbols instead of clean source text.

Expected

Output should only contain readable source files.

If a file is binary, unreadable, or not valid text, code-slicer should skip it and show a warning with the file path.

Actual

The output can contain large blocks of corrupted/binary-looking characters, which makes the generated prompt context unusable.

Suggested fix

Add a guard before printing file contents:

• detect obvious binary/non-text files
• skip them
• print a warning like:

Warning: skipped unreadable or binary file: path/to/file

Acceptance criteria

• Binary/unreadable files are not printed
• A warning identifies skipped files
• Normal source files are still included
• Add a regression test for this case