#[PluginApi]
Attribute on parameters.
Injects the public API (#[PublicApi]) of a plugin into a constructor
parameter of a service: #[PluginApi('my-plugin')] ?NoteApi $notes = null.
The parameter must be nullable with the default null: it receives null if
the plugin is not active. The class is not loaded by the build, so the plugin
may be missing; require it as a development dependency for the IDE and static
analysis. Resolving the service before plugins_loaded is an error, because
not all plugins are loaded then.