feat(radio-group): add helperText and errorText properties (#30222)

Issue number: N/A

---------

## What is the current behavior?
Radio group does not support helper and error text.

## What is the new behavior?
Adds support for helper and error text.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

## Other information

- [Supporting Text:
Preview](https://ionic-framework-git-rou-11554-ionic1.vercel.app/src/components/radio-group/test/supporting-text)

---------

Co-authored-by: Brandy Smith <6577830+brandyscarney@users.noreply.github.com>

packages/angular/standalone/src/directives/radio-group.ts

@@ -16,7 +16,7 @@ import { defineCustomElement } from '@ionic/core/components/ion-radio-group.js';
 
 import { ProxyCmp, proxyOutputs } from './angular-component-lib/utils';
 
-const RADIO_GROUP_INPUTS = ['allowEmptySelection', 'compareWith', 'name', 'value'];
+const RADIO_GROUP_INPUTS = ['allowEmptySelection', 'compareWith', 'errorText', 'helperText', 'name', 'value'];
 
 /**
  * Pulling the provider into an object and using PURE  works