Function createPolicySnapshot

createPolicySnapshot(
    policy: FlowGuardPolicy,
    resolvedAt: string,
    digestFn: (text: string) => string,
    resolution?: {
        requestedMode: PolicyMode;
        effectiveGateBehavior: EffectiveGateBehavior;
        degradedReason?: "ci_context_missing";
        source?: PolicySource;
        resolutionReason?: PolicyResolutionReason;
        centralMinimumMode?: CentralMinimumMode;
        policyDigest?: string;
        policyVersion?: string;
        policyPathHint?: string;
    },
): PolicySnapshot
Create an immutable policy snapshot for embedding in SessionState.

The snapshot freezes all FlowGuard-critical fields. The hash provides non-repudiation: given the hash and the policy registry, an auditor can verify which exact policy governed a session.
Parameters
- policy: FlowGuardPolicy
  The resolved FlowGuard policy.
- resolvedAt: string
  ISO-8601 timestamp when the policy was frozen.
- digestFn: (text: string) => string
  SHA-256 digest function (injected for testability).
- Optionalresolution: {
      requestedMode: PolicyMode;
      effectiveGateBehavior: EffectiveGateBehavior;
      degradedReason?: "ci_context_missing";
      source?: PolicySource;
      resolutionReason?: PolicyResolutionReason;
      centralMinimumMode?: CentralMinimumMode;
      policyDigest?: string;
      policyVersion?: string;
      policyPathHint?: string;
  }
Returns PolicySnapshot
- Defined in config/policy-snapshot.ts:89