[feat] Support auto init YR backend based on metastore

Signed-off-by: Haichuan Hu <kaisennhu@gmail.com>

Author: KaisennHu

transfer_queue/config.yaml

@@ -50,8 +50,14 @@ backend:
   Yuanrong:
     # Whether to let TQ automatically start etcd and datasystem services
     auto_init: True
+    # ========== Etcd mode config ==========
     # etcd service address (used to start etcd when auto_init=true)
     etcd_address: "127.0.0.1:2379"
-    # datasystem worker host and port (used to start dscli when auto_init=true)
-    host: "127.0.0.1"
+    # ========== Metastore mode config ==========
+    # Whether to use metastore mode instead of etcd
+    metastore_mode: False
+    # For auto_init=True, metastore_address is auto-generated on head node
+    # For auto_init=False, specify the external metastore address here
+    metastore_address: ""
+    # Datasystem worker port (host is auto-detected)
     port: 31501