🧑‍💻(admin) add filter and search function to admin mailboxes view

add fields to easily filter and search mailboxes on their statuses,
local part and domains

src/backend/mailbox_manager/admin.py

@@ -61,7 +61,9 @@ class MailDomainAdmin(admin.ModelAdmin):
 class MailboxAdmin(admin.ModelAdmin):
     """Admin for mailbox model."""
 
-    list_display = ("__str__", "first_name", "last_name", "status")
+    list_display = ("__str__", "domain", "status")
+    list_filter = ("status",)
+    search_fields = ("local_part", "domain__name")
 
 
 @admin.register(models.MailDomainAccess)