yaml is in devDependencies but imported at runtime

[nimser]

What happened?

yaml is declared in devDependencies in package.json:56, but the YAML pack loader (src/infrastructure/yaml-pack-loader.ts:2) imports parse from yaml at runtime.

When agent-guardrails is installed as a dependency in a downstream project, devDependencies are not installed. Any consumer who calls loadYamlRulePack / loadAllRulePacks will hit Cannot find module 'yaml' at runtime.

There is no dependencies field in package.json at all.

What did you expect to happen?

yaml should be in dependencies (or peerDependencies) so that consumers who use the YAML loader get it installed automatically.

Steps to reproduce

1. Install the package in a downstream project: npm install agent-guardrails
2. Call loadYamlRulePack(...) from the public API
3. Observe Error: Cannot find module 'yaml'

Relevant log output

Error: Cannot find module 'yaml'
    at .../node_modules/agent-guardrails/dist/infrastructure/yaml-pack-loader.js