feat(api): Human Input Node (backend part) (#31646)

The backend part of the human in the loop (HITL) feature and relevant architecture / workflow engine changes.

Signed-off-by: yihong0618 <zouzou0208@gmail.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: -LAN- <laipz8200@outlook.com>
Co-authored-by: 盐粒 Yanli <yanli@dify.ai>
Co-authored-by: CrabSAMA <40541269+CrabSAMA@users.noreply.github.com>
Co-authored-by: Stephen Zhou <38493346+hyoban@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: yihong <zouzou0208@gmail.com>
Co-authored-by: Joel <iamjoel007@gmail.com>

api/configs/middleware/__init__.py

@@ -6,6 +6,7 @@ from pydantic import Field, NonNegativeFloat, NonNegativeInt, PositiveFloat, Pos
 from pydantic_settings import BaseSettings
 
 from .cache.redis_config import RedisConfig
+from .cache.redis_pubsub_config import RedisPubSubConfig
 from .storage.aliyun_oss_storage_config import AliyunOSSStorageConfig
 from .storage.amazon_s3_storage_config import S3StorageConfig
 from .storage.azure_blob_storage_config import AzureBlobStorageConfig
@@ -317,6 +318,7 @@ class MiddlewareConfig(
     CeleryConfig,  # Note: CeleryConfig already inherits from DatabaseConfig
     KeywordStoreConfig,
     RedisConfig,
+    RedisPubSubConfig,
     # configs of storage and storage providers
     StorageConfig,
     AliyunOSSStorageConfig,