Refactor device management: add vendor field, enhance admin display, and improve MAC address handling

devices/admin.py

@@ -3,4 +3,20 @@ from django.contrib import admin
 # Register your models here.
 from .models import Device
 
-admin.site.register(Device)
+
+class DeviceAdmin(admin.ModelAdmin):
+    list_display = (
+        "id",
+        "user",
+        "mac",
+        "vendor",
+        "blocked_by",
+        "name",
+        "created_at",
+        "updated_at",
+    )
+    search_fields = ("mac", "name")
+    list_filter = ("user",)
+
+
+admin.site.register(Device, DeviceAdmin)