Multiple fields retyped from string to integer/object/array in audit, approval, and protected-env entities

Several fields across three schema definitions have had their declared types corrected/changed in ways that will break clients relying on the previous types:

• API_Entities_AuditEvent: id, author_id, entity_id changed from string → integer (int32); details changed from string → object; created_at gains format: date-time.
• API_Entities_ProtectedEnvironments_ApprovalRuleForSummary: id, user_id, group_id, access_level, required_approvals, group_inheritance_type all changed from string → integer (int32).
• API_Entities_MergeRequestApprovalState (or similar approval entity): approvers and approver_groups changed from string → array of objects.

Any client code that parses these fields as strings or treats approvers/approver_groups as a scalar string will break.