rename project from SimpleshopTheme to Berrypod

All modules, configs, paths, and references updated.
836 tests pass, zero warnings.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/berrypod_web/controllers/cart_controller.ex

@@ -0,0 +1,31 @@
+defmodule BerrypodWeb.CartController do
+  @moduledoc """
+  API controller for cart session persistence.
+
+  LiveView cannot write to session directly, so cart updates are persisted
+  via this API endpoint called from a JS hook after each cart modification.
+  """
+
+  use BerrypodWeb, :controller
+
+  alias Berrypod.Cart
+
+  @doc """
+  Updates the cart in session.
+
+  Expects JSON body with `items` as a list of [variant_id, quantity] arrays.
+  """
+  def update(conn, %{"items" => items}) when is_list(items) do
+    cart_items = Cart.deserialize(items)
+
+    conn
+    |> Cart.put_in_session(cart_items)
+    |> json(%{ok: true})
+  end
+
+  def update(conn, _params) do
+    conn
+    |> put_status(:bad_request)
+    |> json(%{error: "Invalid cart data"})
+  end
+end