chore: generic EventData type for object property

[farfromrefug]

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What is the current behavior?

What is the new behavior?

EventData is now a generic type. This allows us to use EventData<StackLayout> which will say that object is of type StackLayout.
It also comes from some event pre defined generic type. Like LaunchEventData

Fixes/Implements/Closes #[Issue Number].

[farfromrefug]

actually duplicate of this #10193 which handle more cases. I ll close mine