🚀 Playlist: Allow customized PlaylistPage

### Workspace

playlist

### 🔖 Feature description

Similar to how the [PlaylistIndexPage can be customized](https://github.com/backstage/community-plugins/tree/main/workspaces/playlist/plugins/playlist#custom-index-page), it would be really nice if one could also make the PlaylistPage customized.

Something like:
```jsx
}>

```

### 🎤 Context

My team would like to add some security components to the PlaylistPage, and it would be nice not having to fork the whole page to be able to customize it.

### ✌️ Possible Implementation

Same solution that is used for PlaylistIndexPage.

Would also be great if one would export PlaylistEditDialog and PlaylistHeader from the plugin since they are used in the PlaylistPage.

### 👀 Have you spent some time to check if this feature request has been raised before?

- [x] I checked and didn't find similar issue

### 🏢 Have you read the Code of Conduct?

- [x] I have read the [Code of Conduct](https://github.com/backstage/community-plugins/blob/main/CODE_OF_CONDUCT.md)

### Are you willing to submit PR?

No, but I'm happy to collaborate on a PR with someone else