Add cydweb HTML UI preview for catalog cards.

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

firmware/cyd/meta.json

@@ -3,5 +3,14 @@
   "name": "CYD BLE",
   "summary": "NimBLE Nordic UART peripheral with LVGL status UI",
   "description": "Advertise as CYD-BLE with Nordic UART Service. Touch UI: status, scrollable RX/TX log above button bar (Adv / Echo / Ping / Clear). Works with nRF Connect and Serial Bluetooth Terminal.",
-  "tags": ["ble", "nimble", "nus", "uart", "touch"]
+  "tags": [
+    "ble",
+    "nimble",
+    "nus",
+    "uart",
+    "touch"
+  ],
+  "media": {
+    "preview": "media/preview.html"
+  }
 }