Allow to translate inside server actions

[mondeja]

From a conversation on Discord, theorically should be possible to use the context on server actions. But this comes with several problems that need to be solved:

• Is possible to store the I18n context in requests contexts like database pools?
• If so, is implemented for Actix and Axum integrations on Leptos part?
• How to know that we are in a server action when getting the context? That would allow to use the same syntax regardless of the location of the caller.
• Can this only be implemented at the server initialization or can be expanded from the leptos_fluent! macro?