feat(all): add shadow parts to missing components (#21436)

core/src/components/tab-button/readme.md

@@ -232,6 +232,13 @@ export class TabButtonExample {
 | `target`   | `target`   | Specifies where to display the linked URL. Only applies when an `href` is provided. Special keywords: `"_blank"`, `"_self"`, `"_parent"`, `"_top"`.                                                                                                                                       | `string \| undefined`                                                                                   | `undefined` |
 
 
+## Shadow Parts
+
+| Part       | Description                                                   |
+| ---------- | ------------------------------------------------------------- |
+| `"native"` | The native HTML anchor element that wraps all child elements. |
+
+
 ## CSS Custom Properties
 
 | Name                           | Description                                                                                                   |

core/src/components/tab-button/tab-button.tsx

@@ -7,6 +7,8 @@ import { AnchorInterface } from '../../utils/element-interface';
 
 /**
  * @virtualProp {"ios" | "md"} mode - The mode determines which platform styles to use.
+ *
+ * @part native - The native HTML anchor element that wraps all child elements.
  */
 @Component({
   tag: 'ion-tab-button',
@@ -161,7 +163,7 @@ export class TabButton implements ComponentInterface, AnchorInterface {
           'ion-focusable': true
         }}
       >
-        <a {...attrs} tabIndex={-1} class="button-native">
+        <a {...attrs} tabIndex={-1} class="button-native" part="native">
           <span class="button-inner">
             <slot></slot>
           </span>