Add native Microsoft Entra ID support to the Ocean custom integration so it can get and refresh Entra access tokens on its own when calling downstream APIs. Today, customers with Entra-protected APIs have to build the OAuth request by hand with custom auth templates, which only work for self-hosted installs, and manage long-lived client secrets. A dedicated entra_id auth type should support client secret, certificate, Managed Identity, and Workload Identity Federation, with automatic token caching and refresh, for both hosted and self-hosted installs. This would unblock enterprise Azure customers whose security policies require secretless authentication.