Use YAML block scalars (|) for multi-line description fields that contain
<example> blocks with colons and special characters. Without block scalars,
the YAML parser fails because it interprets lines like 'user:' and
'assistant:' as new key-value pairs.
Affected files:
- plugins/plugin-dev/agents/agent-creator.md
- plugins/plugin-dev/agents/skill-reviewer.md
- plugins/plugin-dev/agents/plugin-validator.md
- plugins/pr-review-toolkit/agents/code-simplifier.md
