v0.11.0 — Search, Orders, Wishlist & Image Gallery

Four major features in one release:

- Search — find listings by keyword, category, condition, and price range at

/search. Filters sync to the URL so you can share searches.

- Order History — view all your purchases and sales at /orders with color-coded

status badges and filtering.

- Wishlist — tap the heart on any listing to save it. View your saved items at

/wishlist.

- Image Gallery — listing photos now display in a proper carousel with

thumbnails and a fullscreen lightbox with zoom.

Also hardened authentication by requiring cryptographic wallet signatures on

all requests.