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/routes/__root.tsx

@@ -3,6 +3,7 @@ import { TanStackRouterDevtoolsPanel } from '@tanstack/react-router-devtools'
 import { TanStackDevtools } from '@tanstack/react-devtools'
 
 import appCss from '../styles.css?url'
+import '../styles/globals.scss'
 
 const RootDocument = ({ children }: { children: React.ReactNode }) => (
   <html lang="en">
@@ -38,7 +39,7 @@ export const Route = createRootRoute({
         content: 'width=device-width, initial-scale=1',
       },
       {
-        title: 'TanStack Start Starter',
+        title: 'Ghost Kitchen',
       },
     ],
     links: [