minor #51987 [DoctrineBridge][TwigBridge] Add PHPDoc to attributes (squrious)

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

Discussion
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[DoctrineBridge][TwigBridge] Add PHPDoc to attributes

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | Part of #51920
| License       | MIT

Add PHPDoc to attributes in `Symfony\Bridge\Doctrine` and `Symfony\Bridge\Twig`.

Commits
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d62ebc7615 [DoctrineBridge][TwigBridge] Add PHPDoc to attributes

Author: nicolas-grekas

Attribute/MapEntity.php

@@ -20,6 +20,19 @@
 #[\Attribute(\Attribute::TARGET_PARAMETER)]
 class MapEntity extends ValueResolver
 {
+    /**
+     * @param class-string|null          $class         The entity class
+     * @param string|null                $objectManager Specify the object manager used to retrieve the entity
+     * @param string|null                $expr          An expression to fetch the entity using the {@see https://symfony.com/doc/current/components/expression_language.html ExpressionLanguage} syntax.
+     *                                                  Any request attribute are available as a variable, and your entity repository in the 'repository' variable.
+     * @param array<string, string>|null $mapping       Configures the properties and values to use with the findOneBy() method
+     *                                                  The key is the route placeholder name and the value is the Doctrine property name
+     * @param string[]|null              $exclude       Configures the properties that should be used in the findOneBy() method by excluding
+     *                                                  one or more properties so that not all are used
+     * @param bool|null                  $stripNull     Whether to prevent null values from being used as parameters in the query (defaults to false)
+     * @param string[]|string|null       $id            If an id option is configured and matches a route parameter, then the resolver will find by the primary key
+     * @param bool|null                  $evictCache    If true, forces Doctrine to always fetch the entity from the database instead of cache (defaults to false)
+     */
     public function __construct(
         public ?string $class = null,
         public ?string $objectManager = null,

Validator/Constraints/UniqueEntity.php

@@ -37,8 +37,13 @@ class UniqueEntity extends Constraint
     public bool|array|string $ignoreNull = true;
 
     /**
-     * @param array|string      $fields     The combination of fields that must contain unique values or a set of options
-     * @param bool|array|string $ignoreNull The combination of fields that ignore null values
+     * @param array|string         $fields           The combination of fields that must contain unique values or a set of options
+     * @param bool|string[]|string $ignoreNull       The combination of fields that ignore null values
+     * @param string|null          $em               The entity manager used to query for uniqueness instead of the manager of this class
+     * @param string|null          $entityClass      The entity class to enforce uniqueness on instead of the current class
+     * @param string|null          $repositoryMethod The repository method to check uniqueness instead of findBy. The method will receive as its argument
+     *                                               a fieldName => value associative array according to the fields option configuration
+     * @param string|null          $errorPath        Bind the constraint violation to this field instead of the first one in the fields option configuration
      */
     public function __construct(
         array|string $fields,