feat(comments) : add file attachments on comments

Comments can now have documents attached via multipart/form-data upload.
New endpoint GET /api/documents/comment/{id} to list a comment's files.
Document entity gains a comment relation with cascade remove.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/Entity/Comment.php

@@ -14,6 +14,8 @@ use ApiPlatform\Metadata\GetCollection;
 use ApiPlatform\Metadata\Patch;
 use App\Entity\Trait\CuidEntityTrait;
 use DateTimeImmutable;
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
 use Doctrine\DBAL\Types\Types;
 use Doctrine\ORM\Mapping as ORM;
 
@@ -79,10 +81,15 @@ class Comment
     #[ORM\Column(type: Types::DATETIME_IMMUTABLE, name: 'updated_at')]
     private DateTimeImmutable $updatedAt;
 
+    /** @var Collection<int, Document> */
+    #[ORM\OneToMany(targetEntity: Document::class, mappedBy: 'comment', cascade: ['remove'])]
+    private Collection $documents;
+
     public function __construct()
     {
         $this->createdAt = new DateTimeImmutable();
         $this->updatedAt = new DateTimeImmutable();
+        $this->documents = new ArrayCollection();
     }
 
     public function getContent(): string
@@ -204,4 +211,10 @@ class Comment
 
         return $this;
     }
+
+    /** @return Collection<int, Document> */
+    public function getDocuments(): Collection
+    {
+        return $this->documents;
+    }
 }