Default per-user main.py; invite-only by default

Co-authored-by: Cursor <cursoragent@cursor.com>

src/editor_app/services/user_workspace.py

@@ -0,0 +1,27 @@
+from __future__ import annotations
+
+import re
+from pathlib import Path
+
+from editor_app import config
+
+DEFAULT_MAIN_PY = 'print("Hello, World!")\n'
+
+
+def safe_workspace_leaf(username: str, user_id: int) -> str:
+    base = re.sub(r"[^a-zA-Z0-9._-]+", "-", username.strip()).strip("-").lower() or "user"
+    return f"{base}-{user_id}"
+
+
+def user_workspace_root(user_id: int, username: str, workspace_root: Path | None = None) -> Path:
+    root = (workspace_root or config.WORKSPACE_ROOT).resolve()
+    return root / "users" / safe_workspace_leaf(username, user_id)
+
+
+def ensure_default_code_main(user_root: Path) -> None:
+    """Ensure code/ exists and add a starter main.py when missing."""
+    code_dir = user_root / "code"
+    code_dir.mkdir(parents=True, exist_ok=True)
+    main_py = code_dir / "main.py"
+    if not main_py.exists():
+        main_py.write_text(DEFAULT_MAIN_PY, encoding="utf-8")