Create a mapping between a policy and a resource entity

Policy can be attached to different levels:

1. Table-like level: Policies specific to individual tables or views.
2. Namespace level: Policies applies to a namespace.
3. Catalog level: Policies that applies to a catalog

The ability to attach a policy to a specific entity type is governed by the PolicyValidator. A policy can only be attached if the resource entity is a valid target for the specified policy type.

In addition to the validation rules enforced by the PolicyValidator, there are additional constraints on policy attachment:

1. For inheritable policies, only one policy of the same type can be attached to a given resource entity.
2. For non-inheritable policies, multiple policies of the same type can be attached to the same resource entity without restriction.

For inheritable policies, the inheritance override rule is:

1. Table-like level policies override namespace and catalog policies.
2. Namespace-level policies override upper level namespace or catalog policies.

Additional parameters can be provided in parameters when creating a mapping to define specific behavior or constraints.

If the policy is already attached to the target entity, the existing mapping record will be updated with the new set of parameters, replacing the previous ones.