minor #19506 [DependencyInjection] Add #[Lazy] attribute (Tiriel)

This PR was squashed before being merged into the 7.1 branch.

Discussion
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[DependencyInjection] Add `#[Lazy]` attribute

Fixes #19486
Documentation for the new `#[Lazy]` attribute.

Commits
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6f05767 [DependencyInjection] Add `#[Lazy]` attribute

Author: javiereguiluz

reference/attributes.rst

@@ -37,6 +37,7 @@ Dependency Injection
 * :ref:`AutowireLocator <service-locator_autowire-locator>`
 * :ref:`AutowireServiceClosure <autowiring_closures>`
 * :ref:`Exclude <service-psr4-loader>`
+* :ref:`Lazy <lazy-services_configuration>`
 * :ref:`TaggedIterator <tags_reference-tagged-services>`
 * :ref:`TaggedLocator <service-subscribers-locators_defining-service-locator>`
 * :ref:`Target <autowiring-multiple-implementations-same-type>`

service_container/lazy_services.rst

@@ -124,6 +124,32 @@ laziness, and supports lazy-autowiring of union types::
     ) {
     }
 
+Another possibility is to use the :class:`Symfony\\Component\\DependencyInjection\\Attribute\\Lazy` attribute::
+
+    namespace App\Twig;
+
+    use Symfony\Component\DependencyInjection\Attribute\Lazy;
+    use Twig\Extension\ExtensionInterface;
+
+    #[Lazy]
+    class AppExtension implements ExtensionInterface
+    {
+        // ...
+    }
+
+This attribute can be used on a class or on a parameter which should be lazy-loaded, and has a parameter
+that also supports defining interfaces to proxy and intersection types::
+
+    public function __construct(
+        #[Lazy(FooInterface::class)]
+        FooInterface|BarInterface $foo,
+    ) {
+    }
+
+.. versionadded:: 7.1
+
+    The ``#[Lazy]`` attribute was introduced in Symfony 7.1.
+
 Interface Proxifying
 --------------------