feat(api): add subscription period override fields to subscription update Spec 1.105.23 -> 1.106.0. PatchSubscriptionRequest gains two optional fields (subscription_period_count, subscription_period_interval) on the subscription update endpoint; PatchAddonRequest image_id doc clarified. Purely additive (no removed/required fields) -> minor. The spec's added OPTIONS/docs routes and the doc-only connectors webhook are unconfigured and skipped by generation. - #263