#4779: fix: Add UTF-8 encoding to SKILL.md read operation (fixes #4661)

## Problem Issue #4661 reported a `UnicodeDecodeError` when validating skills on Windows systems. The error occurred because: 1. The skill validation script reads `SKILL.md` files using `Path.read_text()` without specifying an encoding 2. On Windows systems with non-UTF-8 default encoding (e.g., GBK on Chinese Windows), Python defaults to the system encoding 3. When SKILL.md contains UTF-8 characters (like smart quotes, em dashes, or emoji), the GBK decoder fails ## Error ``` UnicodeDecodeError: 'gbk' codec can't decode byte 0x92 in position 822: illegal multibyte sequence ``` ## Solution Added explicit `encoding='utf-8'` parameter to the `read_text()` call in `quick_validate.py`: ```python # Before content = skill_md.read_text() # After content = skill_md.read_text(encoding='utf-8') ``` This ensures consistent UTF-8 handling across all platforms (Windows, macOS, Linux) regardless of system default encoding. ## Testing - ✅ Python syntax validation passes - ✅ One-line change, minimal risk - ✅ Standard Python best practice for reading text files ## Related Fixes #4661 <!-- greptile_comment --> <h2>Greptile Overview</h2> <h3>Greptile Summary</h3> This PR updates the skill validation helper (`skills/skill-creator/scripts/quick_validate.py`) to read `SKILL.md` with an explicit `encoding='utf-8'` when calling `Path.read_text()`. This makes skill validation consistent across platforms and prevents Windows-specific `UnicodeDecodeError` failures when the system default encoding is not UTF-8 (e.g., GBK). <h3>Confidence Score: 5/5</h3> - This PR is safe to merge with minimal risk. - The change is a one-line, narrowly scoped fix that removes platform-dependent default decoding for `SKILL.md` and matches the intended UTF-8 content encoding. - No files require special attention <!-- greptile_other_comments_section --> <!-- /greptile_comment -->