Add zo-icon-generator skill

[Zenlyte]

Description

Adds the zo-icon-generator skill which generates custom themed versions of the Zo Computer logomark while strictly preserving the original shapes and lines.

Features

• Generates custom-themed logomarks
• Maintains original lines and shapes using edit_image

Testing

Tested by using the skill to successfully generate multiple themed versions of the logo.

Checklist

• SKILL.md has required frontmatter (name, description, metadata.author)
• Skill directory name matches name in frontmatter
• Description clearly explains when to use the skill
• No sensitive data (API keys, tokens) included
• bun validate passes

[skeletor-js]

Please fix the template leftovers and resubmit.

• Replace the placeholder author field YOUR_HANDLE.zo.computer.
• Remove any remaining template-style metadata that was not customized.
• Give the submission one final pass for polish and completeness.