feat(demo): add isolated demo environments

apps/demos/management/__init__.py

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+

apps/demos/management/commands/__init__.py

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+

apps/demos/management/commands/cleanup_demo_environments.py

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+from django.core.management.base import BaseCommand
+
+from apps.demos.services import cleanup_expired_demo_environments
+
+
+class Command(BaseCommand):
+    help = "Clean up expired isolated demo environments."
+
+    def add_arguments(self, parser):
+        parser.add_argument("--expired", action="store_true", help="Clean expired demo environments.")
+        parser.add_argument("--batch-size", type=int, default=None, help="Maximum number of environments to clean.")
+
+    def handle(self, *args, **options):
+        if not options["expired"]:
+            self.stderr.write("Only --expired cleanup is supported.")
+            return
+        cleaned = cleanup_expired_demo_environments(batch_size=options["batch_size"])
+        self.stdout.write(self.style.SUCCESS(f"Cleaned {cleaned} expired demo environment(s)."))