Function resolve_commit_policy 

pub fn resolve_commit_policy(
    cluster_default: CommitPolicy,
    collection_override: Option<CommitPolicy>,
    model: CollectionDataModel,
    ha_intent: HaIntent,
) -> Result<CommitPolicyResolution, CommitPolicyViolation>

Deterministically resolve the effective commit policy for one collection.

cluster_default is the global default; collection_override is the collection’s declared override (if any); model is the collection’s durability model; ha_intent is whether the deployment declared HA intent.

Returns the resolved policy, or CommitPolicyViolation when the guardrail rejects a durable model degraded to local-only acknowledgement under HA intent. The function is pure and side-effect free.