[makspll]

Elements handle bevy_picking's pointer events, instead of polling the deprecated Interaction component.

ui.node({
    on_click = function(event) print(event.button, event.x, event.y) end,
    on_press = ..., on_release = ...,
    on_pointer_enter = ..., on_pointer_leave = ...,
    on_hover = function(over) ... end,          -- both of the above, given whether the pointer is over the element
    on_drag = function(event) print(event.delta_x, event.delta_y) end,
    on_scroll = ...,
})

• one observer per pointer event (events.rs) queues the handler of the entity the event is at. Handlers run in the next flush, in their script's context, as before
• the innermost element with a handler for an event gets it, the event does not bubble further. An element without one lets it through to its ancestors
• handlers are given the event after their dependencies and (in a row template) the row's item: { x, y, button, count, delta_x, delta_y } as the event has them
• ui.interact(entity, "click") does what a pointer event on the element would, for tests and for driving a ui without a pointer (it takes the event names now: "press" is on_press)
• elements with handlers no longer need an extra component, picking finds nodes itself

Rune checks argument counts, so its handlers declare the event: |selected, name, _event| ...

Not covered by a test: the observers themselves (the tests go through ui.interact), there is no pointer in the headless test app.

Stacked on #728.

[semanticdiff-com]

Review changes with  

Changed Files

File	Status
assets/tests/reactive_ui/inventory/inventory.lua	70% smaller
crates/bevy_mod_scripting_reactive_ui/src/runtime.rs	23% smaller
crates/bevy_mod_scripting_reactive_ui/src/lib.rs	20% smaller
crates/bevy_mod_scripting_reactive_ui/src/style.rs	2% smaller
assets/macro_benchmarks/reactive_ui/closures.lua	0% smaller
assets/macro_benchmarks/reactive_ui/inventory.rn	Unsupported file format
assets/macro_benchmarks/reactive_ui/paths.lua	0% smaller
assets/macro_benchmarks/reactive_ui/template.lua	0% smaller
assets/tests/reactive_ui/inventory_rune/inventory.rn	Unsupported file format
crates/bevy_mod_scripting_reactive_ui/Cargo.toml	Unsupported file format
crates/bevy_mod_scripting_reactive_ui/src/events.rs	0% smaller

[github-actions]

Bencher Report

Project	Bevy Scripting
Branch	agent/reactive-ui-events
Testbed	linux-gha

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[github-actions]

Bencher Report

Project	Bevy Scripting
Branch	agent/reactive-ui-events
Testbed	linux-gha

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