Delete an endpoint and its targets, immediately or by staging the removal in the line's draft with commitMode "draft" and draftRevision (returns {draft} instead of deleting right away). An immediate delete publishes a new revision without the endpoint and returns {deleted: true, endpointId}, but the line's prior revision still has it, so list_config_revisions can find that revision and rollback_config can republish over the deletion. Errors when lineKey/endpointId is missing, the line or endpoint doesn't exist, the draft revision is stale, removing the endpoint would leave an active line with no endpoints, or the publish is refused (a rejected target mapping or an outbound-allowlist violation is a validation error; a publish the platform could not verify is retryable). Requires edit access.