Refactor Field components with const arrow functions (#1261)

## Summary
- convert all remaining Field components to const arrow functions
- document the refactor in the CHANGELOG

## Testing
- `npm run lint`
- `npm run build`


------
https://chatgpt.com/codex/tasks/task_e_68684db1b6b88331837307a54e3f9dc1

src/components/FieldJson.tsx

@@ -1,12 +1,11 @@
-import React from 'react'
 import InputJson, {InputJsonProps} from './InputJson'
 
 
 type FieldJsonProps = InputJsonProps & {};
 
 
-export default class FieldJson extends React.Component<FieldJsonProps> {
-  render() {
-    return <InputJson {...this.props} />
-  }
-}
+const FieldJson: React.FC<FieldJsonProps> = (props) => {
+  return <InputJson {...props} />;
+};
+
+export default FieldJson;