Implement Create/Drop Index/Metadata index in GO (#13791)

### What problem does this PR solve?

Implement Create/Drop Index/Metadata index in GO

New API handling in GO:
POST/kb/index 
DELETE /kb/index
POST /tenant/doc_meta_index
DELETE /tenant/doc_meta_index

CREATE INDEX FOR DATASET 'dataset_name' VECTOR_SIZE 1024;
DROP INDEX FOR DATASET 'dataset_name';
CREATE INDEX DOC_META;
DROP INDEX DOC_META;

### Type of change

- [x] Refactoring

internal/cli/types.go

@@ -98,6 +98,9 @@ const (
 	TokenToken
 	TokenTokens
 	TokenUnset
+	TokenIndex
+	TokenVectorSize
+	TokenDocMeta
 
 	// Literals
 	TokenIdentifier