Add a more expressive condition language for controls #88

Summary

• Add a more expressive condition language for controls so a single control can combine multiple conditions.

Motivation

• Some policies need to reason over more than one condition at once, and splitting that logic across several controls is awkward and harder to manage.

Current behavior

• A control effectively captures a single condition, so more complex logic has to be modeled across multiple controls or pushed into evaluator internals.

Expected behavior

• A control should be able to express multiple conditions in one place with clear composition semantics.

Reproduction (if bug)

1. N/A
2. This is a feature request.
3. N/A

Proposed solution (optional)

• Introduce a more expressive control condition model, likely supporting boolean composition such as and, or, and not, while keeping authoring simple.