Change plugin name from 'hub-guide' to 'code-guide' to avoid AI
interpreting it as Hub-specific. Skills now show as code-guide:skill-name.
Universal best-practice, not limited to any specific project.
- hooks.json needs 'hooks' wrapper key at top level
- Remove 'hooks' field from plugin.json (auto-discovered from hooks/hooks.json)
- Simplify hook entries (no nested hooks array)