Make bevy_window and bevy_input events serializable

[alice-i-cecile]

What problem does this solve or what need does it fill?

All of the events in this file should be serializable, in order to enable effective playback of window events for testing.

Similarly, many events in bevy_input are not serializable.

What solution would you like?

Add derives for Serialize and Deserialize, controlled by an off-by-default feature flag.

[emersonmx]

Hello.
I started to see this issue, but I can't tell what should be serialized or not in bevy_input.
I found this too, but I don't know if I need to put it in all struct of touch.rs or if only in those that are commented out as an event. Example: A touch input event.

[alice-i-cecile]

Hmm, good question. WRT touch data, it's hard to say, as I haven't experimented with Bevy on touch devices yet. For my purposes, I think TouchInput is the only critical one.

[alice-i-cecile]

Reopening so we can tackle touch input events too.

[emersonmx]

Hello again 👋🏻
The only places I could find to put "serialize" were TouchInput and ForceTouch.