✨ Feature: Add feature: Support model-level cooling. When a model under a channel reports an error, it does not affect other models under the same channel, only the model that reported the error is cooled.
✨ Feature: Add feature: Support channel cooldown. When an API channel response fails, the channel will automatically be excluded and cooled down for a period of time, during which no requests will be made to that channel. After the cooldown period ends, the model will automatically be restored until it fails again, triggering another cooldown.