Major updates: - fix(gateway): fix SSE streaming usage data overwrite issue - feat(purchase): add purchase subscription iframe page and config - fix(scheduler): fix race condition from empty cache - feat(settings): add PurchaseSubscriptionEnabled and PurchaseSubscriptionURL Resolved conflicts: - backend/cmd/server/VERSION: updated to 0.1.61 - setting_service.go: keep TianShuAPI site name while adding purchase subscription features Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>