Release v1.6.8
fix: Replace GITHUB_TOKEN with PERSONAL_TOKEN to resolve release workflow permissions
- Fix 'Resource not accessible by integration' error in GitHub Actions
- Update all release-related steps to use Personal Access Token (PERSONAL_TOKEN)
- Improve release workflow reliability and permissions handling
- Ensure consistent release creation across all scenarios
- Update CHANGELOG.md with v1.6.8 release notes
This resolves the insufficient permissions issue when creating releases and uploading assets.