Extend Subscription Trial

Extend the free trial for a subscription item.

This endpoint is intended for admin use only. It allows extending the trial period for a specific subscription item to a new end date.

Args: subscription_item_id: The ID of the subscription item to extend body: Request body containing the new trial end date request: FastAPI request object user_id: User ID (injected by @require_auth) org_id: Organization ID (injected by @require_auth)

Returns: Updated subscription item data

Raises: HTTPException: If the operation fails