Fixed inspection issues

src/Entity/Parts/Part.php

@@ -103,13 +103,13 @@ class Part extends AttachmentContainingDBElement
     protected $attachments;
 
     /**
-     * @var DateTime the date when this element was modified the last time
+     * @var DateTime|null the date when this element was modified the last time
      * @ORM\Column(type="datetime", name="last_modified", options={"default":"CURRENT_TIMESTAMP"})
      */
     protected ?DateTime $lastModified = null;
 
     /**
-     * @var Attachment
+     * @var Attachment|null
      * @ORM\ManyToOne(targetEntity="App\Entity\Attachments\Attachment")
      * @ORM\JoinColumn(name="id_preview_attachment", referencedColumnName="id", onDelete="SET NULL", nullable=true)
      * @Assert\Expression("value == null or value.isPicture()", message="part.master_attachment.must_be_picture")

src/Entity/Parts/PartTraits/AdvancedPropertyTrait.php

@@ -55,7 +55,7 @@ trait AdvancedPropertyTrait
     protected ?float $mass = null;
 
     /**
-     * @var string The internal part number of the part
+     * @var string|null The internal part number of the part
      * @ORM\Column(type="string", length=100, nullable=true, unique=true)
      * @Assert\Length(max="100")
      * @Groups({"extended", "full", "import"})

src/Entity/Parts/PartTraits/BasicPropertyTrait.php

@@ -59,7 +59,7 @@ trait BasicPropertyTrait
     protected bool $favorite = false;
 
     /**
-     * @var Category The category this part belongs too (e.g. Resistors). Use tags, for more complex grouping.
+     * @var Category|null The category this part belongs too (e.g. Resistors). Use tags, for more complex grouping.
      *               Every part must have a category.
      * @ORM\ManyToOne(targetEntity="Category")
      * @ORM\JoinColumn(name="id_category", referencedColumnName="id", nullable=false)

src/Entity/Parts/PartTraits/ManufacturerTrait.php

@@ -59,7 +59,7 @@ trait ManufacturerTrait
     protected string $manufacturer_product_number = '';
 
     /**
-     * @var string The production status of this part. Can be one of the specified ones.
+     * @var string|null The production status of this part. Can be one of the specified ones.
      * @ORM\Column(type="string", length=255, nullable=true)
      * @Assert\Choice({"announced", "active", "nrfnd", "eol", "discontinued", ""})
      * @Groups({"extended", "full", "import"})

src/Entity/Parts/PartTraits/OrderTrait.php

@@ -57,7 +57,7 @@ trait OrderTrait
     protected bool $manual_order = false;
 
     /**
-     * @var Orderdetail
+     * @var Orderdetail|null
      * @ORM\OneToOne(targetEntity="App\Entity\PriceInformations\Orderdetail")
      * @ORM\JoinColumn(name="order_orderdetails_id", referencedColumnName="id")
      */