- Add project‑scoped stack support to the file‑state backend with automatic enablement and an environment‑variable opt‑out.
- Introduce `pulumi state upgrade` CLI subcommand to migrate self‑managed state to the new project layout.
- Fix CLI display panic on small terminals, correct whitespace errors in generated .csproj files, and add a warning for non‑project stacks in a project‑scoped backend.