Tie back the Joke Shop curtain bays and add the describe_image vision tool

docs/screens/boards/jokeshop-day-board.json

@@ -1,6 +1,6 @@
 {
   "board": "jokeshop-day-board.jpg",
-  "caption": "Joke Shop frontage, day. Photo: local-only research frame (tmp/research/comedy-store). Concept: photo-anchored (gemini + gpt). Capture: dark stucco wall tile + white signature band.",
+  "caption": "Joke Shop frontage, day. Photo: local-only research frame (tmp/research/comedy-store). Concept: photo-anchored (gemini + gpt). Capture: dark stucco wall tile + white signature band + tied-back curtain bays.",
   "photo": "tmp/research/comedy-store/01.jpg",
   "concept": "docs/screens/concepts/joke_shop/joke_shop_entrance_day-v2.png",
   "capture": "docs/screenshots/12-joke-shop.png"