Feat: Import & export the agents. #3851 (#3894)

### What problem does this PR solve?

Feat: Import & export the agents. #3851

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/locales/en.ts

@@ -1077,6 +1077,8 @@ When you want to search the given knowledge base at first place, set a higher pa
       ccEmailTip: 'cc_email: CC email (Optional)',
       subjectTip: 'subject: Email subject (Optional)',
       contentTip: 'content: Email content (Optional)',
+      jsonUploadTypeErrorMessage: 'Please upload json file',
+      jsonUploadContentErrorMessage: 'json file error',
     },
     footer: {
       profile: 'All rights reserved @ React',