Put document metadata in ES/Infinity (#12826)

### What problem does this PR solve?

Put document metadata in ES/Infinity.

Index name of meta data: ragflow_doc_meta_{tenant_id}

### Type of change

- [x] Refactoring

conf/doc_meta_es_mapping.json

@@ -0,0 +1,29 @@
+{
+  "settings": {
+    "index": {
+      "number_of_shards": 2,
+      "number_of_replicas": 0,
+      "refresh_interval": "1000ms"
+    }
+  },
+  "mappings": {
+    "_source": {
+      "enabled": true
+    },
+    "dynamic": "runtime",
+    "properties": {
+      "id": {
+        "type": "keyword",
+        "store": true
+      },
+      "kb_id": {
+        "type": "keyword",
+        "store": true
+      },
+      "meta_fields": {
+        "type": "object",
+        "dynamic": true
+      }
+    }
+  }
+}

conf/doc_meta_infinity_mapping.json

@@ -0,0 +1,5 @@
+{
+  "id": {"type": "varchar", "default": ""},
+  "kb_id": {"type": "varchar", "default": ""},
+  "meta_fields": {"type": "json", "default": "{}"}
+}