Automatically registers an event to be added to the app.
# Parameters
- `plugin = PluginType` - Required unless the `default_plugin` feature is enabled and `#[auto_plugin(default_plugin)]` is in scope. Specifies which plugin should register this event.
- `after_build` - Optional. Injects this macro's tokens at the end of the plugin build instead of the start.
- `generics(T1, T2, ...)` - Optional. Specifies concrete types for generic parameters.
When provided, the event will be registered with these specific generic parameters.
Note: Clippy will complain if you have duplicate generic type names. For those you can use named generics: `generics(A = ..., B = ...)`.
- `derive` | `derive(Debug, Default, ..)` - Optional. Specifies that the macro should handle deriving `Message`.
Passes through any additional derives listed.
- `reflect` | `reflect(Debug, Default, ..)` - Optional. Specifies that the macro should handle emitting the single `#[reflect(...)]`.
Passes through any additional reflects listed.
If enabled in tandem with `derive` it also includes `#[derive(Reflect)]`
- `register` - Enables type registration for the `Resource`
Same as having `#[auto_register_type]`
# Example
```rust
use bevy::prelude::*;
use bevy_auto_plugin::prelude::*;
#[derive(AutoPlugin)]
#[auto_plugin(impl_plugin_trait)]
struct MyPlugin;
#[auto_event(plugin = MyPlugin, derive(Debug, Default, PartialEq), reflect, register)]
struct FooEvent(usize);
```
# Example (with generics)
```rust
use bevy::prelude::*;
use bevy_auto_plugin::prelude::*;
#[derive(AutoPlugin)]
#[auto_plugin(impl_plugin_trait)]
struct MyPlugin;
#[auto_event(plugin = MyPlugin, generics(usize), derive(Debug, Default, PartialEq), reflect, register)]
struct FooEventWithGeneric<T>(T);
```