Are there any plans to implement prepared writes?

I'm currently working on a websocket-based broadcasting server and would be more then happy to use this great library, but there is no prepared writes functionality, like in some other websocket libraries (e.g. [gorilla/websocket](https://github.com/gorilla/websocket) and [lxzan/gws](https://github.com/lxzan/gws/tree/main)). This would help a lot to optimize the broadcasting of identical messages. Are there any plans to implement this feature in some way (or accept PRs that implements it)?

I'm not sure how the API should look like, but it would be cool to have something similar.
```Go
var connections []*websocket.Conn

// Create prepared message without frames generation.
pm := websocket.PrepareMessage(websocket.MessageText, []byte("hello"))
defer pm.Close()

for _, c := range connections {
// Lazily initialize frame buffer for "pm" and reuse it for other connections.
// For each set of compression settings (mode and threshold), there will be separate pre-initialized frame
// buffers, so if some connections don't have compression enabled and some do have, then two types of
// frame buffers will be initialized for each of them.
if err := c.WritePrepared(ctx, pm); err != nil {
log.Printf("failed to write prepared message: %v\n", err)
}
}
````

Commencez par examiner l’API d’écriture existante de websocket.Conn dans la bibliothèque ainsi que les points d’entrée proposés PrepareMessage et WritePrepared, puis comparez le comportement cité de gorilla/websocket et lxzan/gws. Établissez l’API, les interactions avec la compression et le cycle de vie des messages avant l’implémentation ; le travail est considéré comme terminé lorsqu’un design validé prend en charge la réutilisation pour des broadcasts identiques.

Rédigé par le modèle d'indexation à partir du texte de l'issue.