feat: add comprehensive GitHub workflow and development tools

app/manage.py

@@ -0,0 +1,11 @@
+#!/usr/bin/env python
+import os
+import sys
+
+def main():
+    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'core.settings')
+    from django.core.management import execute_from_command_line
+    execute_from_command_line(sys.argv)
+
+if __name__ == '__main__':
+    main()