Add the customer ordering page

Builds the main customer-facing flow: browse the Brand's menu, add
items to a cart, and check out either as a guest (name + contact) or,
if signed in, as the account customer — both call the existing
placeOrder server function, which already distinguishes the two. On
success, navigates to a new /orders/$orderId status page showing each
Order Item's Preparation Steps, queue position, ETA, and (per the
domain rules already established) a Cancel button while cancellable
and a pickup-confirmation button once ready.

Styled with SCSS Modules per CLAUDE.md; added the sass dependency and
the src/styles/ structure it describes (globals.scss imported once in
__root.tsx, alongside the existing Tailwind stylesheet the not-yet-
mounted header-user.tsx component depends on).

Verified end-to-end against a throwaway local Postgres: menu renders
with seeded items, cart quantities update, guest checkout places a
real order, and the status page reflects a real cancellation.

Also fixes CLAUDE.md's Commands section, which documented pnpm even
though this repo only has npm (package-lock.json, no pnpm installed).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/components/ordering/MenuList.module.scss

@@ -0,0 +1,68 @@
+@use '../../styles/variables' as *;
+
+.list {
+  list-style: none;
+  margin: 0;
+  padding: 0;
+  display: flex;
+  flex-direction: column;
+  gap: $space-3;
+}
+
+.item {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: $space-3;
+  padding: $space-3;
+  border: 1px solid $color-border;
+  border-radius: $radius;
+  background: $color-surface;
+}
+
+.info {
+  flex: 1;
+}
+
+.name {
+  margin: 0 0 $space-1;
+  font-size: 1.1rem;
+}
+
+.description {
+  margin: 0 0 $space-1;
+  color: $color-text-muted;
+  font-size: 0.9rem;
+}
+
+.meta {
+  margin: 0;
+  font-size: 0.85rem;
+  color: $color-text-muted;
+}
+
+.quantity {
+  display: flex;
+  align-items: center;
+  gap: $space-2;
+}
+
+.stepperButton {
+  width: 2rem;
+  height: 2rem;
+  border-radius: 50%;
+  border: 1px solid $color-border;
+  background: $color-background;
+  cursor: pointer;
+
+  &:disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+  }
+}
+
+.count {
+  min-width: 1.5rem;
+  text-align: center;
+  font-variant-numeric: tabular-nums;
+}