memory: detail-plate toolchain, prompt-refusal gotcha, floating-window fix

MEMORY.md

@@ -418,3 +418,25 @@ Scope: facts and traps that cost time to establish. Planned work lives in [TODO.
 - Rebuilt hero → re-imported (`SM_HeroFacade`, bounds 2604 × 1257 × 1450 cm) →
   DemoMap rebuilt → screenshots re-rendered. Note `ue_hero_facade_import.py` saves
   the map, so `chmod u+w` the `.umap` first or the import silently does not persist.
+
+## 2026-11-09 — AI detail plates from reference photos; floating windows fixed
+
+- `Tools/facade_detail_concepts.py` generates architectural detail plates from one
+  local reference photograph via OpenRouter image models (default
+  `google/gemini-2.5-flash-image`; the sibling project uses the same route in
+  `tools/generate_textures.py` — chat/completions with a text + image_url content
+  part, image returned as `message.images[].image_url.url`). Eight studies,
+  `--list` free, `--all` generates, `-vN` never overwrites, `.refgen.json` sidecar
+  per image, all output under gitignored `Art/reference/facade-details/`.
+- **Prompt gotcha:** the model refuses when the prompt describes features the
+  reference photograph does not show ("the image you sent appears to be a
+  decorative architectural detail, not an entrance with steps"). Prompts must
+  describe the *reference subject* and only restage light/people/surface.
+- **Output is real:** 1184×864 to 1344×768 PNGs, ~2 MB each.
+- **Measured defect found and fixed:** hero window panes sat at Y −1.98 while the
+  mass front is Y −0.50 and the columns reach −1.02 — i.e. glazing floating 1.44 m
+  in front of the wall and ahead of the colonnade. Now `WINDOW_Y = −0.56`
+  (6 cm proud of the wall, behind the columns). Visible as dark openings in
+  `review-hero-facade-front`.
+- Reminder: `.blend` is LFS read-only on checkout — `chmod u+w` or Blender fails
+  with "Cannot save blend file … not writable" (this bit again here).