feat: add get all metadata support

I have added new metadata route to get all the metadata. Please
note I have not tested this route aa there was time shortage and the
route was not available during the development of this route.

Also, I have fixed the `getMetadata` name. It was previously known as
`retrieveMetadata`.

fixes: https://contentstack.atlassian.net/browse/CS-32161

Author: Deepak-Kharah

src/metadata.ts

@@ -1,3 +1,5 @@
+import { AnyObject } from "./types/common.types";
+
 export declare interface IMetadata {
     uid: string;
     type: "asset" | "entry";
@@ -26,7 +28,8 @@ export declare interface IMetadataDeleteDto {
 
 const metadataTypes = {
     creteMetadata: "createMetadata",
-    retrieveMetadata: "retrieveMetadata",
+    retrieveMetadata: "getMetadata",
+    retrieveAllMetadata: "getAllMetadata",
     updateMetadata: "updateMetadata",
     deleteMetadata: "deleteMetadata",
 } as const;
@@ -67,6 +70,17 @@ class Metadata {
         return this._connection.sendToParent("stackQuery", data);
     }
 
+    retrieveAllMetaData(metadataConfig: AnyObject) {
+        const data = {
+            action: metadataTypes.retrieveAllMetadata,
+            payload: {
+                ...metadataConfig
+            },
+        };
+
+        return this._connection.sendToParent("stackQuery", data);
+    }
+
     updateMetaData(metadataConfig: IMetadataUpdateDto) {
         const { uid, ...otherMetaData } = metadataConfig;