init_skill.py fails due to missing PyYAML

Summary

Running skill-creator scaffolding now fails because the local init_skill.py depends on PyYAML and the environment lacks the module.

Feedback thread ID: 019c6b94-7d48-78f0-82dc-ead92e07620d

Reproduction

1. Execute:

``bash
python3 /Users/prb/.codex/skills/.system/skill-creator/scripts/init_skill.py release-sync-new-ui --path /Users/prb/.codex/skills --resources scripts --interface "display_name=Release + Sync new-ui" --interface "short_description=Run prb-effect release, verify npm publish, then bump and migrate in new-ui." --interface "default_prompt=Run just release in prb-effect, verify the new version is on npm, stop if it is not, then update dependencies in ~/sablier/new-ui and migrate code to the new package syntax/features."
``

1. Script exits with:

``
Traceback ...
ModuleNotFoundError: No module named 'yaml'
``

Expected

Skill creation should proceed without a missing dependency error.

Actual

The script aborts because PyYAML cannot be imported.

Environment

• Codex CLI version: 0.101.0
• OS: Darwin MacBook-Pro-14-2024 25.3.0 (xnu-12377.81.4~5/RELEASE_ARM64_T6041 arm64)
• Python: 3.12.11
• Shell: /bin/zsh

Impact

I had to manually scaffold the skill directory instead of using init_skill.py.

[!WARNING] This is blocking for skill creation in this environment until the dependency is made explicit or bundled.