Validate a policy configuration before applying it.

Checks:

• All referenced guardrails exist in the guardrail registry
• All non-wildcard team aliases exist in the database
• All non-wildcard key aliases exist in the database
• Inheritance chains are valid (no cycles, parents exist)
• Scope patterns are syntactically valid

Returns:

• valid: True if the policy configuration is valid (no blocking errors)
• errors: List of blocking validation errors
• warnings: List of non-blocking validation warnings

Example request:

{
    "policies": {
        "global-baseline": {
            "guardrails": {
                "add": ["pii_blocker", "phi_blocker"]
            },
            "scope": {
                "teams": ["*"],
                "keys": ["*"],
                "models": ["*"]
            }
        },
        "healthcare-compliance": {
            "inherit": "global-baseline",
            "guardrails": {
                "add": ["hipaa_audit"]
            },
            "scope": {
                "teams": ["healthcare-team"]
            }
        }
    }
}