Add Rich-powered CLI + raw-Python tool-protection decorator

[Sunny-commit]

Goal

Ship the first DX milestone:

• opendecision CLI that loads a decision-pack YAML, evaluates supplied JSON state through DecisionGuard, and renders decision + confidence + probabilities + provider + limitations.
• Framework-agnostic raw-Python decorator for tool protection (allow/review/block patterns).

Requirements

• Rich is optional (lazy import; core install remains lightweight).
• Preserve lazy Laya loading (CLI should not import Laya unless actually running with default provider).
• Unit tests that run without model downloads.
• Update packaging + README.

Acceptance

• python -m opendecision ... works without Rich.
• opendecision ... uses Rich when installed.
• Tests cover CLI parse + output shape + decorator behavior with a fake provider.