bug: Vue IonTabBar and IonButtons missing slot prop type

### Prerequisites

- [x] I have read the [Contributing Guidelines](https://github.com/ionic-team/ionic-framework/blob/main/docs/CONTRIBUTING.md#creating-an-issue).
- [x] I agree to follow the [Code of Conduct](https://ionicframework.com/code-of-conduct).
- [x] I have searched for [existing issues](https://github.com/ionic-team/ionic-framework/issues) that already report this problem, without success.

### Ionic Framework Version

v8.x

### Current Behavior

In a Vue application with a strict templates vue-tsc preset (that disallows undefined properties to be set), using the `IonTabBar` or `IonButtons` with a named slot (for example `slot="bottom"`) leads to a TypeScript error.

This is due to the fact that vue-tsc doesn't recognise a `slot` prop.
There may be more components with the same issue.

### Expected Behavior

I expect the component definition to include the `slot` property.

### Steps to Reproduce

In a vue project with vue-tsc's configuration set like so (part of tsconfig.json)
```json
"vueCompilerOptions": {
"strictTemplates": true
}
```

Add this to any vue component's template:

```

Home

```

### Code Reproduction URL

https://stackblitz.com/edit/vue-kq5gzqta?file=package.json,src%2Fcomponents%2FHelloWorld.vue,tsconfig.json

### Ionic Info

Ionic:

Ionic CLI : 7.2.0
Ionic Framework : @ionic/vue 8.6.2

Capacitor:

Capacitor CLI : not installed
@capacitor/android : 7.4.0
@capacitor/core : 7.4.0
@capacitor/ios : 7.4.0

Utility:

cordova-res : not installed globally
native-run : 2.0.1

System:

NodeJS : v20.17.0
npm : 11.0.0
OS : macOS Unknown

### Additional Information

_No response_

Start from the Vue component typings for IonTabBar and IonButtons and reproduce the strictTemplates error using the linked StackBlitz project. Check how the slot attribute is represented in the component definitions, then verify that named-slot usage type-checks under vue-tsc with strictTemplates for both components.

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