Bump to v0.2.1 (maintenance): CI now verifies the NSIS installer contents via 7z

- Add a 'Verify Windows installer contents' step (7z l shows Step Line.exe +
  uninstall.exe) so the TODO verification items are proven by CI output
- Rebuild 0.2.1 binaries (embedded PCK) and AppImage locally; smoke clean;
  57/57 tests

DONE.md

@@ -185,6 +185,13 @@ Completed task sections moved from `TODO.md`. Sections are moved only when every
       Follow-up: anonymous **asset downloads** require sign-in on this host (host setting).
 - [x] CI packaging follow-up was already live (`.gitea/workflows/build.yml` on tags).
 
+## 🎨 AI texture generation (OpenRouter)
+
+- [x] Extend `tools/generate_textures.py` with an OpenRouter image-API mode (`--ai`, `--prompt`,
+      `--name`, `--model`, `--size`), decoding base64 PNG responses and clamping to ≤1024px.
+- [x] Verify a live `--ai` generation against a real `OPENROUTER_API_KEY` (generated
+      `ai/…` set at 1024×1024; seedream minimum-pixel by requesting 2048 and downscaling.
+
 ## 🧹 Runtime hygiene + timeline/polish items
 
 - [x] RefCounted cycle cleanup: `FSM` now holds its owner via `WeakRef`; `ShiftCoordinator` is