feat(custom-fields) : add machineContextOnly flag and link FKs for machine context

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

src/Entity/CustomField.php

@@ -55,6 +55,10 @@ class CustomField
     #[Groups(['composant:read', 'piece:read', 'product:read', 'machine:read'])]
     private bool $required = false;
 
+    #[ORM\Column(type: Types::BOOLEAN, options: ['default' => false], name: 'machinecontextonly')]
+    #[Groups(['composant:read', 'piece:read', 'product:read', 'machine:read'])]
+    private bool $machineContextOnly = false;
+
     #[ORM\Column(type: Types::STRING, length: 255, nullable: true, name: 'defaultValue')]
     private ?string $defaultValue = null;
 
@@ -220,4 +224,16 @@ class CustomField
 
         return $this;
     }
+
+    public function isMachineContextOnly(): bool
+    {
+        return $this->machineContextOnly;
+    }
+
+    public function setMachineContextOnly(bool $machineContextOnly): static
+    {
+        $this->machineContextOnly = $machineContextOnly;
+
+        return $this;
+    }
 }